LAVAA

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Off on a Comet! a Journey through Planetary Space by Jules Verne, is part of the HackerNoon Books Series. You can jump to any chapter in this book . A CARRIER-PIGEON here CHAPTER XXIII. A CARRIER-PIGEON When, three hours after sunset, on the 23d of March, the Gallian moon rose upon the western horizon, it was observed that she had entered upon her last quarter. She had taken only four days to pass from syzygy to quadrature, and it was consequently evident that she would be visible for little more than a week at a time, and that her lunation would be accomplished within sixteen days. The lunar months, like the solar days, had been diminished by one-half. Three days later the moon was in conjunction with the sun, and was consequently lost to view; Ben Zoof, as the first observer of the satellite, was extremely interested in its movements, and wondered whether it would ever reappear. On the 26th, under an atmosphere perfectly clear and dry, the thermometer fell to 12 degrees F. below zero. Of the present distance of Gallia from the sun, and the number of leagues she had traversed since the receipt of the last mysterious document, there were no means of judging; the extent of diminution in the apparent disc of the sun did not afford sufficient basis even for an approximate calculation; and Captain Servadac was perpetually regretting that they could receive no further tidings from the anonymous correspondent, whom he persisted in regarding as a fellow-countryman. The solidity of the ice was perfect; the utter stillness of the air at the time when the final congelation of the waters had taken place had resulted in the formation of a surface that for smoothness would rival a skating-rink; without a crack or flaw it extended far beyond the range of vision. The contrast to the ordinary aspect of polar seas was very remarkable. There, the ice-fields are an agglomeration of hummocks and icebergs, massed in wild confusion, often towering higher than the masts of the largest whalers, and from the instability of their foundations liable to an instantaneous loss of equilibrium; a breath of wind, a slight modification of the temperature, not unfrequently serving to bring about a series of changes outrivaling the most elaborate transformation scenes of a pantomime. Here, on the contrary, the vast white plain was level as the desert of Sahara or the Russian steppes; the waters of the Gallian Sea were imprisoned beneath the solid sheet, which became continually stouter in the increasing cold. Accustomed to the uneven crystallizations of their own frozen seas, the Russians could not be otherwise than delighted with the polished surface that afforded them such excellent opportunity for enjoying their favorite pastime of skating. A supply of skates, found hidden away amongst the stores, was speedily brought into use. The Russians undertook the instruction of the Spaniards, and at the end of a few days, during which the temperature was only endurable through the absence of wind, there was not a Gallian who could not skate tolerably well, while many of them could describe figures involving the most complicated curves. Nina and Pablo earned loud applause by their rapid proficiency; Captain Servadac, an adept in athletics, almost outvied his instructor, the count; and Ben Zoof, who had upon some rare occasions skated upon the Lake of Montmartre (in his eyes, of course, a sea), performed prodigies in the art. Dobryna’s This exercise was not only healthful in itself, but it was acknowledged that, in case of necessity, it might become a very useful means of locomotion. As Captain Servadac remarked, it was almost a substitute for railways, and as if to illustrate this proposition, Lieutenant Procope, perhaps the greatest expert in the party, accomplished the twenty miles to Gourbi Island and back in considerably less than four hours. The temperature, meanwhile, continued to decrease, and the average reading of the thermometer was about 16 degrees F. below zero; the light also diminished in proportion, and all objects appeared to be enveloped in a half-defined shadow, as though the sun were undergoing a perpetual eclipse. It was not surprising that the effect of this continuously overhanging gloom should be to induce a frequent depression of spirits amongst the majority of the little population, exiles as they were from their mother earth, and not unlikely, as it seemed, to be swept far away into the regions of another planetary sphere. Probably Count Timascheff, Captain Servadac, and Lieutenant Procope were the only members of the community who could bring any scientific judgment to bear upon the uncertainty that was before them, but a general sense of the strangeness of their situation could not fail at times to weigh heavily upon the minds of all. Under these circumstances it was very necessary to counteract the tendency to despond by continual diversion; and the recreation of skating thus opportunely provided, seemed just the thing to arouse the flagging spirits, and to restore a wholesome excitement. With dogged obstinacy, Isaac Hakkabut refused to take any share either in the labors or the amusements of the colony. In spite of the cold, he had not been seen since the day of his arrival from Gourbi Island. Captain Servadac had strictly forbidden any communication with him; and the smoke that rose from the cabin chimney of the was the sole indication of the proprietor being still on board. There was nothing to prevent him, if he chose, from partaking gratuitously of the volcanic light and heat which were being enjoyed by all besides; but rather than abandon his close and personal oversight of his precious cargo, he preferred to sacrifice his own slender stock of fuel. Hansa Both the schooner and the tartan had been carefully moored in the way that seemed to promise best for withstanding the rigor of the winter. After seeing the vessels made secure in the frozen creek. Lieutenant Procope, following the example of many Arctic explorers, had the precaution to have the ice beveled away from the keels, so that there should be no risk of the ships’ sides being crushed by the increasing pressure; he hoped that they would follow any rise in the level of the ice-field, and when the thaw should come, that they would easily regain their proper water-line. On his last visit to Gourbi Island, the lieutenant had ascertained that north, east, and west, far as the eye could reach, the Gallian Sea had become one uniform sheet of ice. One spot alone refused to freeze; this was the pool immediately below the central cavern, the receptacle for the stream of burning lava. It was entirely enclosed by rocks, and if ever a few icicles were formed there by the action of the cold, they were very soon melted by the fiery shower. Hissing and spluttering as the hot lava came in contact with it, the water was in a continual state of ebullition, and the fish that abounded in its depths defied the angler’s craft; they were, as Ben Zoof remarked, “too much boiled to bite.” At the beginning of April the weather changed. The sky became overcast, but there was no rise in the temperature. Unlike the polar winters of the earth, which ordinarily are affected by atmospheric influence, and liable to slight intermissions of their severity at various shiftings of the wind, Gallia’s winter was caused by her immense distance from the source of all light and heat, and the cold was consequently destined to go on steadily increasing until it reached the limit ascertained by Fourier to be the normal temperature of the realms of space. With the over-clouding of the heavens there arose a violent tempest; but although the wind raged with an almost inconceivable fury, it was unaccompanied by either snow or rain. Its effect upon the burning curtain that covered the aperture of the central hall was very remarkable. So far from there being any likelihood of the fire being extinguished by the vehemence of the current of air, the hurricane seemed rather to act as a ventilator, which fanned the flame into greater activity, and the utmost care was necessary to avoid being burnt by the fragments of lava that were drifted into the interior of the grotto. More than once the curtain itself was rifted entirely asunder, but only to close up again immediately after allowing a momentary draught of cold air to penetrate the hall in a way that was refreshing and rather advantageous than otherwise. On the 4th of April, after an absence of about four days, the new satellite, to Ben Zoof’s great satisfaction, made its reappearance in a crescent form, a circumstance that seemed to justify the anticipation that henceforward it would continue to make a periodic revolution every fortnight. The crust of ice and snow was far too stout for the beaks of the strongest birds to penetrate, and accordingly large swarms had left the island, and, following the human population, had taken refuge on the volcanic promontory; not that there the barren shore had anything in the way of nourishment to offer them, but their instinct impelled them to haunt now the very habitations which formerly they would have shunned. Scraps of food were thrown to them from the galleries; these were speedily devoured, but were altogether inadequate in quantity to meet the demand. At length, emboldened by hunger, several hundred birds ventured through the tunnel, and took up their quarters actually in Nina’s Hive. Congregating in the large hall, the half-famished creatures did not hesitate to snatch bread, meat, or food of any description from the hands of the residents as they sat at table, and soon became such an intolerable nuisance that it formed one of the daily diversions to hunt them down; but although they were vigorously attacked by stones and sticks, and even occasionally by shot, it was with some difficulty that their number could be sensibly reduced. By a systematic course of warfare the bulk of the birds were all expelled, with the exception of about a hundred, which began to build in the crevices of the rocks. These were left in quiet possession of their quarters, as not only was it deemed advisable to perpetuate the various breeds, but it was found that these birds acted as a kind of police, never failing either to chase away or to kill any others of their species who infringed upon what they appeared to regard as their own special privilege in intruding within the limits of their domain. On the 15th loud cries were suddenly heard issuing from the mouth of the principal gallery. “Help, help! I shall be killed!” Pablo in a moment recognized the voice as Nina’s. Outrunning even Ben Zoof he hurried to the assistance of his little playmate, and discovered that she was being attacked by half a dozen great sea-gulls, and only after receiving some severe blows from their beaks could he succeed by means of a stout cudgel in driving them away. “Tell me, Nina, what is this?” he asked as soon as the tumult had subsided. The child pointed to a bird which she was caressing tenderly in her bosom. “A pigeon!” exclaimed Ben Zoof, who had reached the scene of commotion, adding: “A carrier-pigeon! And by all the saints of Montmartre, there is a little bag attached to its neck!” He took the bird, and rushing into the hall placed it in Servadac’s hands. “Another message, no doubt,” cried the captain, “from our unknown friend. Let us hope that this time he has given us his name and address.” All crowded round, eager to hear the news. In the struggle with the gulls the bag had been partially torn open, but still contained the following dispatch: “Gallia! Chemin parcouru du 1er Mars au 1er Avril: 39,000,000 l.! Distance du soleil: 110,000,000 l.! Capte Nerina en passant. Vivres vont manquer et...” The rest of the document had been so damaged by the beaks of the gulls that it was illegible. Servadac was wild with vexation. He felt more and more convinced that the writer was a Frenchman, and that the last line indicated that he was in distress from scarcity of food. The very thought of a fellow-countryman in peril of starvation drove him well-nigh to distraction, and it was in vain that search was made everywhere near the scene of conflict in hopes of finding the missing scrap that might bear a signature or address. Suddenly little Nina, who had again taken possession of the pigeon, and was hugging it to her breast, said: “Look here, Ben Zoof!” And as she spoke she pointed to the left wing of the bird. The wing bore the faint impress of a postage-stamp, and the one word: “FORMENTERA.” About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Jules Verne (1998). Off on a Comet! a Journey through Planetary Space. Urbana, Illinois: Project Gutenberg. Retrieved October 2022 https://www.gutenberg.org/cache/epub/1353/pg1353-images.html This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at , located at . www.gutenberg.org https://www.gutenberg.org/policy/license.html

A CARRIER-PIGEON

A Journey to the Center of the Earth by Jules Verne, is part of the HackerNoon Books Series. You can jump to any chapter in this book . THE EASTERN TUNNEL here CHAPTER XVI - THE EASTERN TUNNEL The next day was Tuesday, the 30th of June—and at six o'clock in the morning we resumed our journey. We still continued to follow the gallery of lava, a perfect natural pathway, as easy of descent as some of those inclined planes which, in very old German houses, serve the purpose of staircases. This went on until seventeen minutes past twelve, the precise instant at which we rejoined Hans, who, having been somewhat in advance, had suddenly stopped. "At last," cried my uncle, "we have reached the end of the shaft." I looked wonderingly about me. We were in the centre of four cross paths—somber and narrow tunnels. The question now arose as to which it was wise to take; and this of itself was no small difficulty. My uncle, who did not wish to appear to have any hesitation about the matter before myself or the guide, at once made up his mind. He pointed quietly to the eastern tunnel; and, without delay, we entered within its gloomy recesses. Besides, had he entertained any feeling of hesitation it might have been prolonged indefinitely, for there was no indication by which to determine on a choice. It was absolutely necessary to trust to chance and good fortune! The descent of this obscure and narrow gallery was very gradual and winding. Sometimes we gazed through a succession of arches, its course very like the aisles of a Gothic cathedral. The great artistic sculptors and builders of the Middle Ages might have here completed their studies with advantage. Many most beautiful and suggestive ideas of architectural beauty would have been discovered by them. After passing through this phase of the cavernous way, we suddenly came, about a mile farther on, upon a square system of arch, adopted by the early Romans, projecting from the solid rock, and keeping up the weight of the roof. Suddenly we would come upon a series of low subterranean tunnels which looked like beaver holes, or the work of foxes—through whose narrow and winding ways we had literally to crawl! The heat still remained at quite a supportable degree. With an involuntary shudder, I reflected on what the heat must have been when the volcano of Sneffels was pouring its smoke, flames, and streams of boiling lava—all of which must have come up by the road we were now following. I could imagine the torrents of hot seething stone darting on, bubbling up with accompaniments of smoke, steam, and sulphurous stench! "Only to think of the consequences," I mused, "if the old volcano were once more to set to work." I did not communicate these rather unpleasant reflections to my uncle. He not only would not have understood them, but would have been intensely disgusted. His only idea was to go ahead. He walked, he slid, he clambered over piles of fragments, he rolled down heaps of broken lava, with an earnestness and conviction it was impossible not to admire. At six o'clock in the evening, after a very wearisome journey, but one not so fatiguing as before, we had made six miles towards the southward, but had not gone more than a mile downwards. My uncle, as usual, gave the signal to halt. We ate our meal in thoughtful silence, and then retired to sleep. Our arrangements for the night were very primitive and simple. A traveling rug, in which each rolled himself, was all our bedding. We had no necessity to fear cold or any unpleasant visit. Travelers who bury themselves in the wilds and depths of the African desert, who seek profit and pleasure in the forests of the New World, are compelled to take it in turn to watch during the hours of sleep; but in this region of the earth absolute solitude and complete security reigned supreme. We had nothing to fear either from savages or from wild beasts. After a night's sweet repose, we awoke fresh and ready for action. There being nothing to detain us, we started on our journey. We continued to burrow through the lava tunnel as before. It was impossible to make out through what soil we were making way. The tunnel, moreover, instead of going down into the bowels of the earth, became absolutely horizontal. I even thought, after some examination, that we were actually tending upwards. About ten o'clock in the day this state of things became so clear that, finding the change very fatiguing, I was obliged to slacken my pace and finally come to a halt. "Well," said the Professor quickly, "what is the matter?" "The fact is, I am dreadfully tired," was my earnest reply. "What," cried my uncle, "tired after a three hours' walk, and by so easy a road?" "Easy enough, I dare say, but very fatiguing." "But how can that be, when all we have to do is to go downwards." "I beg your pardon, sir. For some time I have noticed that we are going upwards." "Upwards," cried my uncle, shrugging his shoulders, "how can that be?" "There can be no doubt about it. For the last half hour the slopes have been upward—and if we go on in this way much longer we shall find ourselves back in Iceland." My uncle shook his head with the air of a man who does not want to be convinced. I tried to continue the conversation. He would not answer me, but once more gave the signal for departure. His silence I thought was only caused by concentrated ill-temper. However this might be, I once more took up my load, and boldly and resolutely followed Hans, who was now in advance of my uncle. I did not like to be beaten or even distanced. I was naturally anxious not to lose sight of my companions. The very idea of being left behind, lost in that terrible labyrinth, made me shiver as with the ague. Besides, if the ascending path was more arduous and painful to clamber, I had one source of secret consolation and delight. It was to all appearance taking us back to the surface of the earth. That of itself was hopeful. Every step I took confirmed me in my belief, and I began already to build castles in the air in relation to my marriage with my pretty little cousin. About twelve o'clock there was a great and sudden change in the aspect of the rocky sides of the gallery. I first noticed it from the diminution of the rays of light which cast back the reflection of the lamp. From being coated with shining and resplendent lava, it became living rock. The sides were sloping walls, which sometimes became quite vertical. We were now in what the geological professors call a state of transition, in the period of Silurian stones, so called because this specimen of early formation is very common in England in the counties formerly inhabited by the Celtic nation known as Silures. "I can see clearly now," I cried; "the sediment from the waters which once covered the whole earth formed during the second period of its existence these schists and these calcareous rocks. We are turning our backs on the granite rocks, and are like people from Hamburg who would go to Lubeck by way of Hanover." I might just as well have kept my observations to myself. My geological enthusiasm got the better, however, of my cooler judgment, and Professor Hardwigg heard my observations. "What is the matter now?" he said, in a tone of great gravity. "Well," cried I, "do you not see these different layers of calcareous rocks and the first indication of slate strata?" "Well; what then?" "We have arrived at that period of the world's existence when the first plants and the first animals made their appearance." "You think so?" "Yes, look; examine and judge for yourself." I induced the Professor with some difficulty to cast the light of his lamp on the sides of the long winding gallery. I expected some exclamation to burst from his lips. I was very much mistaken. The worthy Professor never spoke a word. It was impossible to say whether he understood me or not. Perhaps it was possible that in his pride—my uncle and a learned professor—he did not like to own that he was wrong in having chosen the eastern tunnel, or was he determined at any price to go to the end of it? It was quite evident we had left the region of lava, and that the road by which we were going could not take us back to the great crater of Mount Sneffels. As we went along I could not help ruminating on the whole question, and asked myself if I did not lay too great a stress on these sudden and peculiar modifications of the earth's crust. After all, I was very likely to be mistaken—and it was within the range of probability and possibility that we were not making our way through the strata of rocks which I believed I recognized piled on the lower layer of granitic formation. "At all events, if I am right," I thought to myself, "I must certainly find some remains of primitive plants, and it will be absolutely necessary to give way to such indubitable evidence. Let us have a good search." I accordingly lost no opportunity of searching, and had not gone more than about a hundred yards, when the evidence I sought for cropped up in the most incontestable manner before my eyes. It was quite natural that I should expect to find these signs, for during the Silurian period the seas contained no fewer than fifteen hundred different animal and vegetable species. My feet, so long accustomed to the hard and arid lava soil, suddenly found themselves treading on a kind of soft dust, the remains of plants and shells. Upon the walls themselves I could clearly make out the outline, as plain as a sun picture, of the fucus and the lycopods. The worthy and excellent Professor Hardwigg could not of course make any mistake about the matter; but I believe he deliberately closed his eyes, and continued on his way with a firm and unalterable step. I began to think that he was carrying his obstinacy a great deal too far. I could no longer act with prudence or composure. I stooped on a sudden and picked up an almost perfect shell, which had undoubtedly belonged to some animal very much resembling some of the present day. Having secured the prize, I followed in the wake of my uncle. "Do you see this?" I said. "Well, said the Professor, with the most imperturbable tranquillity, "it is the shell of a crustaceous animal of the extinct order of the trilobites; nothing more, I assure you." "But," cried I, much troubled at his coolness, "do you draw no conclusion from it?" "Well, if I may ask, what conclusion do you draw from it yourself?" "Well, I thought—" "I know, my boy, what you would say, and you are right, perfectly and incontestably right. We have finally abandoned the crust of lava and the road by which the lava ascended. It is quite possible that I may have been mistaken, but I shall be unable to discover my error until I get to the end of this gallery." "You are quite right as far as that is concerned," I replied, "and I should highly approve of your decision, if we had not to fear the greatest of all dangers." "And what is that?" "Want of water." "Well, my dear Henry, it can't be helped. We must put ourselves on rations." And on he went. About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Jules Verne (2006). A Journey to the Center of the Earth. Urbana, Illinois: Project Gutenberg. Retrieved October 2022 https://www.gutenberg.org/files/18857/18857-h/18857-h.htm This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at , located at . www.gutenberg.org https://www.gutenberg.org/policy/license.html

THE EASTERN TUNNEL

The Story-book of Science by Jean-Henri Fabre, is part of the HackerNoon Books Series. You can jump to any chapter in this book here . CATANIA CHAPTER XLVI. CATANIA “YESTERDAY,” Uncle Paul resumed, “Jules asked me if the lava-streams could not reach towns situated near volcanoes. The following story will answer his question. It is about an eruption of Mount Etna.” “Etna is that volcano in Sicily where the big chestnut tree of a hundred horses is?” asked Claire. “Yes. I must tell you that two hundred years ago there occurred in Sicily one of the most terrible eruptions on record. During the night, after a furious storm, the earth began to tremble so violently that a great many houses fell. Trees swayed like reeds shaken by the wind; people, fleeing distracted into the country to avoid being crushed under the ruins of their buildings, lost their footing on the quaking ground, stumbled, and fell. At that moment Etna burst in a fissure four leagues long, and along this fissure rose a number of volcanic mouths, vomiting, amid the crash of frightful detonations, clouds of black smoke and calcined sand. Soon seven of these mouths united in an abyss that for four months did not cease thundering, glowing, and throwing up cinders and lava. The crater of Etna, at first quite at rest, as if its furnaces had no connection with the new volcanic mouths, woke up a few days after and threw to a prodigious height a column of flames and smoke; then the whole mountain shook, and all the crests that dominated its crater fell into the depths of the volcano. The next day four mountaineers dared to climb to the top of Etna. They found the crater very much enlarged by the falling-in of the day before: its orifice, which before had measured one league, now measured two. “In the meantime, torrents of lava were pouring from all the crevasses of the mountain down upon the plain, destroying houses, forests, and crops. Some leagues from the volcano, on the seacoast, lies Catania, a large town surrounded then by strong walls. Already the liquid fire had devoured several villages, when the stream reached the walls of Catania and spread over the country. There, as if to show its strength to the terrified Catanians, it tore a hill away and transported it some distance; it lifted in one mass a field planted with vines and let it float for some time, until the green was reduced to charcoal and disappeared. Finally, the fiery stream reached a wide and deep valley. The Catanians believed themselves saved: no doubt the volcano would exhaust its strength by the time it covered the vast basin which the lava had just entered. But what an error of judgment! In the short space of six hours, the valley was filled, and the lava, overflowing, advanced straight toward the town in a stream half a league wide and ten meters high. It would have been all over with Catania if, by the luckiest chance, another current, whose direction crossed the first, had not come and struck against the fiery flood and turned it from its course. The stream, thus turned, coasted the ramparts of the town within pistol-shot, and turned toward the sea.” “I was very much afraid for those poor Catanians,” interposed Emile, “when you spoke of that wall of fire, high as a house, going straight toward the town.” “All is not over yet,” his uncle proceeded. “The stream, I told you, was going toward the sea. There was, then, a formidable battle between the water and the fire. The lava presented a perpendicular front of 1500 meters in extent and a dozen meters high. At the touch of that burning wall, which continued plunging further and further into the waves, enormous masses of vapor rose with horrible hissings, darkened the sky with their thick clouds, and fell in a salt rain over all the region. In a few days the lava had made the limits of the shore recede three hundred meters. “In spite of that, Catania was still menaced. The stream, swollen with new tributaries, grew from day to day and approached the town. From the top of the walls the inhabitants followed with terror the implacable progress of the scourge. The lava finally reached the ramparts. The fiery flood rose slowly, but it rose ceaselessly; from hour to hour it was found to have risen a little higher. It touched the top of the walls, whereupon, yielding to the pressure, they were overthrown for the length of forty meters, and the stream of fire penetrated the town.” “My goodness!” cried Claire. “Those poor people are lost?” “No, not the people, for lava runs very slowly, on account of its sticky nature, and one can be warned in time; it was the town itself that ran the greatest risk. The quarters invaded by the lava were the highest; from there the current could spread everywhere. So Catania seemed destined to total destruction, when it was saved by the courage of some men who attempted to battle with the volcano. They bethought themselves to construct stone walls, which, placed across the route of the on-coming stream, would change its direction. This device partly succeeded, but the following was the most efficacious. Lava streams envelop themselves in a kind of solid sheath, embank themselves in a canal formed of blocks coagulated and welded together. Under this covering the melted matter preserves its fluidity and continues its ravaging course. They thought, then, that by breaking these natural dikes at a well-chosen spot, they would open to the lava a new route across country and would thus turn it from the town. Followed by a hundred alert and vigorous men, they attacked the stream, not far from the volcano, with blows of iron bars. The heat was so great that each worker could strike only two or three blows in succession, after which he withdrew to recover his breath. However, they managed to make a breach in the solid sheath, when, as they had foreseen, the lava flowed through this opening. Catania was saved, not without great loss, for already the lava flood had consumed, within the town walls, three hundred houses and some palaces and churches. Outside of Catania, this eruption, so sadly celebrated, covered from five to six square leagues with a bed of lava in some places thirteen meters thick, and destroyed the homes of twenty-seven thousand persons.” “Without those brave men who did not hesitate, at the risk of being burnt alive, to go and open a new passage for the stream of fire, Catania would certainly have been lost,” remarked Jules. “Catania would have been all burnt down, there is no doubt. To-day its calcined ruins would be buried under a bed of cold lava, and there would be nothing left but the name of the large town that had disappeared. Three or four stout-hearted men revive the courage of the terrified population; they hope that heaven will aid them in their devotion, and, ready to sacrifice their lives, they prevent the frightful disaster. Ah! may God give you grace, my dear child, to imitate them in the time of danger; for, you see, if man is great through his intelligence, he is still greater through his heart. In my old age, when I hear you spoken of, I shall be more gladdened by the good you may have done than by the knowledge you may have acquired. Knowledge, my little friend, is only a better means of aiding others. Remember that well, and when you are a man bear yourself in danger as did those of Catania. I ask it of you in return for my love and my stories.” Jules furtively wiped away a tear. His uncle perceived that he had sown his word in good ground. About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. Jean-Henri Fabre (2018). The Story-book of Science. Urbana, Illinois: Project Gutenberg. Retrieved https://www.gutenberg.org/cache/epub/56795/pg56795-images.html This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org , located at https://www.gutenberg.org/policy/license.html.

Etna is that volcano in Sicily

ST. JAGO, IN THE CAPE DE VERDE ARCHIPELAGO

The Island of Doctor Moreau, by H. G. Wells, is part of the HackerNoon Books Series. You can jump to any chapter in this book here . XII. THE SAYERS OF THE LAW XII. THE SAYERS OF THE LAW Then something cold touched my hand. I started violently, and saw close to me a dim pinkish thing, looking more like a flayed child than anything else in the world. The creature had exactly the mild but repulsive features of a sloth, the same low forehead and slow gestures. As the first shock of the change of light passed, I saw about me more distinctly. The little sloth-like creature was standing and staring at me. My conductor had vanished. The place was a narrow passage between high walls of lava, a crack in the knotted rock, and on either side interwoven heaps of sea-mat, palm-fans, and reeds leaning against the rock formed rough and impenetrably dark dens. The winding way up the ravine between these was scarcely three yards wide, and was disfigured by lumps of decaying fruit-pulp and other refuse, which accounted for the disagreeable stench of the place. The little pink sloth-creature was still blinking at me when my Ape-man reappeared at the aperture of the nearest of these dens, and beckoned me in. As he did so a slouching monster wriggled out of one of the places, further up this strange street, and stood up in featureless silhouette against the bright green beyond, staring at me. I hesitated, having half a mind to bolt the way I had come; and then, determined to go through with the adventure, I gripped my nailed stick about the middle and crawled into the little evil-smelling lean-to after my conductor. It was a semi-circular space, shaped like the half of a bee-hive; and against the rocky wall that formed the inner side of it was a pile of variegated fruits, cocoa-nuts among others. Some rough vessels of lava and wood stood about the floor, and one on a rough stool. There was no fire. In the darkest corner of the hut sat a shapeless mass of darkness that grunted “Hey!” as I came in, and my Ape-man stood in the dim light of the doorway and held out a split cocoa-nut to me as I crawled into the other corner and squatted down. I took it, and began gnawing it, as serenely as possible, in spite of a certain trepidation and the nearly intolerable closeness of the den. The little pink sloth-creature stood in the aperture of the hut, and something else with a drab face and bright eyes came staring over its shoulder. “Hey!” came out of the lump of mystery opposite. “It is a man.” “It is a man,” gabbled my conductor, “a man, a man, a five-man, like me.” “Shut up!” said the voice from the dark, and grunted. I gnawed my cocoa-nut amid an impressive stillness. I peered hard into the blackness, but could distinguish nothing. “It is a man,” the voice repeated. “He comes to live with us?” It was a thick voice, with something in it—a kind of whistling overtone—that struck me as peculiar; but the English accent was strangely good. The Ape-man looked at me as though he expected something. I perceived the pause was interrogative. “He comes to live with you,” I said. “It is a man. He must learn the Law.” I began to distinguish now a deeper blackness in the black, a vague outline of a hunched-up figure. Then I noticed the opening of the place was darkened by two more black heads. My hand tightened on my stick. The thing in the dark repeated in a louder tone, “Say the words.” I had missed its last remark. “Not to go on all-fours; that is the Law,” it repeated in a kind of sing-song. I was puzzled. “Say the words,” said the Ape-man, repeating, and the figures in the doorway echoed this, with a threat in the tone of their voices. I realised that I had to repeat this idiotic formula; and then began the insanest ceremony. The voice in the dark began intoning a mad litany, line by line, and I and the rest to repeat it. As they did so, they swayed from side to side in the oddest way, and beat their hands upon their knees; and I followed their example. I could have imagined I was already dead and in another world. That dark hut, these grotesque dim figures, just flecked here and there by a glimmer of light, and all of them swaying in unison and chanting, “Not to go on all-fours; that is the Law. Are we not Men? “Not to suck up Drink; that is the Law. Are we not Men? “Not to eat Fish or Flesh; that is the Law. Are we not Men? “Not to claw the Bark of Trees; that is the Law. Are we not Men? “Not to chase other Men; that is the Law. Are we not Men?” And so from the prohibition of these acts of folly, on to the prohibition of what I thought then were the maddest, most impossible, and most indecent things one could well imagine. A kind of rhythmic fervour fell on all of us; we gabbled and swayed faster and faster, repeating this amazing Law. Superficially the contagion of these brutes was upon me, but deep down within me the laughter and disgust struggled together. We ran through a long list of prohibitions, and then the chant swung round to a new formula. “His is the House of Pain. “His is the Hand that makes. “His is the Hand that wounds. “His is the Hand that heals.” And so on for another long series, mostly quite incomprehensible gibberish to me about Him, whoever he might be. I could have fancied it was a dream, but never before have I heard chanting in a dream. “His is the lightning flash,” we sang. “His is the deep, salt sea.” A horrible fancy came into my head that Moreau, after animalising these men, had infected their dwarfed brains with a kind of deification of himself. However, I was too keenly aware of white teeth and strong claws about me to stop my chanting on that account. “His are the stars in the sky.” At last that song ended. I saw the Ape-man’s face shining with perspiration; and my eyes being now accustomed to the darkness, I saw more distinctly the figure in the corner from which the voice came. It was the size of a man, but it seemed covered with a dull grey hair almost like a Skye-terrier. What was it? What were they all? Imagine yourself surrounded by all the most horrible cripples and maniacs it is possible to conceive, and you may understand a little of my feelings with these grotesque caricatures of humanity about me. “He is a five-man, a five-man, a five-man—like me,” said the Ape-man. I held out my hands. The grey creature in the corner leant forward. “Not to run on all-fours; that is the Law. Are we not Men?” he said. He put out a strangely distorted talon and gripped my fingers. The thing was almost like the hoof of a deer produced into claws. I could have yelled with surprise and pain. His face came forward and peered at my nails, came forward into the light of the opening of the hut and I saw with a quivering disgust that it was like the face of neither man nor beast, but a mere shock of grey hair, with three shadowy over-archings to mark the eyes and mouth. “He has little nails,” said this grisly creature in his hairy beard. “It is well.” He threw my hand down, and instinctively I gripped my stick. “Eat roots and herbs; it is His will,” said the Ape-man. “I am the Sayer of the Law,” said the grey figure. “Here come all that be new to learn the Law. I sit in the darkness and say the Law.” “It is even so,” said one of the beasts in the doorway. “Evil are the punishments of those who break the Law. None escape.” “None escape,” said the Beast Folk, glancing furtively at one another. “None, none,” said the Ape-man,—“none escape. See! I did a little thing, a wrong thing, once. I jabbered, jabbered, stopped talking. None could understand. I am burnt, branded in the hand. He is great. He is good!” “None escape,” said the grey creature in the corner. “None escape,” said the Beast People, looking askance at one another. “For every one the want that is bad,” said the grey Sayer of the Law. “What you will want we do not know; we shall know. Some want to follow things that move, to watch and slink and wait and spring; to kill and bite, bite deep and rich, sucking the blood. It is bad. ‘Not to chase other Men; that is the Law. Are we not Men? Not to eat Flesh or Fish; that is the Law. Are we not Men?’” “None escape,” said a dappled brute standing in the doorway. “For every one the want is bad,” said the grey Sayer of the Law. “Some want to go tearing with teeth and hands into the roots of things, snuffing into the earth. It is bad.” “None escape,” said the men in the door. “Some go clawing trees; some go scratching at the graves of the dead; some go fighting with foreheads or feet or claws; some bite suddenly, none giving occasion; some love uncleanness.” “None escape,” said the Ape-man, scratching his calf. “None escape,” said the little pink sloth-creature. “Punishment is sharp and sure. Therefore learn the Law. Say the words.” And incontinently he began again the strange litany of the Law, and again I and all these creatures began singing and swaying. My head reeled with this jabbering and the close stench of the place; but I kept on, trusting to find presently some chance of a new development. “Not to go on all-fours; that is the Law. Are we not Men?” We were making such a noise that I noticed nothing of a tumult outside, until some one, who I think was one of the two Swine Men I had seen, thrust his head over the little pink sloth-creature and shouted something excitedly, something that I did not catch. Incontinently those at the opening of the hut vanished; my Ape-man rushed out; the thing that had sat in the dark followed him (I only observed that it was big and clumsy, and covered with silvery hair), and I was left alone. Then before I reached the aperture I heard the yelp of a staghound. In another moment I was standing outside the hovel, my chair-rail in my hand, every muscle of me quivering. Before me were the clumsy backs of perhaps a score of these Beast People, their misshapen heads half hidden by their shoulder-blades. They were gesticulating excitedly. Other half-animal faces glared interrogation out of the hovels. Looking in the direction in which they faced, I saw coming through the haze under the trees beyond the end of the passage of dens the dark figure and awful white face of Moreau. He was holding the leaping staghound back, and close behind him came Montgomery revolver in hand. For a moment I stood horror-struck. I turned and saw the passage behind me blocked by another heavy brute, with a huge grey face and twinkling little eyes, advancing towards me. I looked round and saw to the right of me and a half-dozen yards in front of me a narrow gap in the wall of rock through which a ray of light slanted into the shadows. “Stop!” cried Moreau as I strode towards this, and then, “Hold him!” At that, first one face turned towards me and then others. Their bestial minds were happily slow. I dashed my shoulder into a clumsy monster who was turning to see what Moreau meant, and flung him forward into another. I felt his hands fly round, clutching at me and missing me. The little pink sloth-creature dashed at me, and I gashed down its ugly face with the nail in my stick and in another minute was scrambling up a steep side pathway, a kind of sloping chimney, out of the ravine. I heard a howl behind me, and cries of “Catch him!” “Hold him!” and the grey-faced creature appeared behind me and jammed his huge bulk into the cleft. “Go on! go on!” they howled. I clambered up the narrow cleft in the rock and came out upon the sulphur on the westward side of the village of the Beast Men. That gap was altogether fortunate for me, for the narrow chimney, slanting obliquely upward, must have impeded the nearer pursuers. I ran over the white space and down a steep slope, through a scattered growth of trees, and came to a low-lying stretch of tall reeds, through which I pushed into a dark, thick undergrowth that was black and succulent under foot. As I plunged into the reeds, my foremost pursuers emerged from the gap. I broke my way through this undergrowth for some minutes. The air behind me and about me was soon full of threatening cries. I heard the tumult of my pursuers in the gap up the slope, then the crashing of the reeds, and every now and then the crackling crash of a branch. Some of the creatures roared like excited beasts of prey. The staghound yelped to the left. I heard Moreau and Montgomery shouting in the same direction. I turned sharply to the right. It seemed to me even then that I heard Montgomery shouting for me to run for my life. Presently the ground gave rich and oozy under my feet; but I was desperate and went headlong into it, struggled through kneedeep, and so came to a winding path among tall canes. The noise of my pursuers passed away to my left. In one place three strange, pink, hopping animals, about the size of cats, bolted before my footsteps. This pathway ran up hill, across another open space covered with white incrustation, and plunged into a canebrake again. Then suddenly it turned parallel with the edge of a steep-walled gap, which came without warning, like the ha-ha of an English park,—turned with an unexpected abruptness. I was still running with all my might, and I never saw this drop until I was flying headlong through the air. I fell on my forearms and head, among thorns, and rose with a torn ear and bleeding face. I had fallen into a precipitous ravine, rocky and thorny, full of a hazy mist which drifted about me in wisps, and with a narrow streamlet from which this mist came meandering down the centre. I was astonished at this thin fog in the full blaze of daylight; but I had no time to stand wondering then. I turned to my right, down-stream, hoping to come to the sea in that direction, and so have my way open to drown myself. It was only later I found that I had dropped my nailed stick in my fall. Presently the ravine grew narrower for a space, and carelessly I stepped into the stream. I jumped out again pretty quickly, for the water was almost boiling. I noticed too there was a thin sulphurous scum drifting upon its coiling water. Almost immediately came a turn in the ravine, and the indistinct blue horizon. The nearer sea was flashing the sun from a myriad facets. I saw my death before me; but I was hot and panting, with the warm blood oozing out on my face and running pleasantly through my veins. I felt more than a touch of exultation too, at having distanced my pursuers. It was not in me then to go out and drown myself yet. I stared back the way I had come. I listened. Save for the hum of the gnats and the chirp of some small insects that hopped among the thorns, the air was absolutely still. Then came the yelp of a dog, very faint, and a chattering and gibbering, the snap of a whip, and voices. They grew louder, then fainter again. The noise receded up the stream and faded away. For a while the chase was over; but I knew now how much hope of help for me lay in the Beast People. About HackerNoon Book Series: We bring you the most important technical, scientific, and insightful public domain books. This book is part of the public domain. H. G. Wells (1994). The Island of Doctor Moreau. Urbana, Illinois: Project Gutenberg. Retrieved October 2022, from https://www.gutenberg.org/files/159/159-h/159-h.htm This eBook is for the use of anyone anywhere at no cost and with almost no restrictions whatsoever. You may copy it, give it away or re-use it under the terms of the Project Gutenberg License included with this eBook or online at www.gutenberg.org , located at https://www.gutenberg.org/policy/license.html.

The Island of Doctor Moreau: XII. THE SAYERS OF THE LAW

is a 1990 bullet hell shoot-em-up game released for the Atari ST and Commodore Amiga 16-bit computers, developed by Eclipse Software and published by Thalion Software. What is unique about this game is that it came on a “dual boot” floppy diskette, which allowed two separate versions of the same game to coexist on the same disk together, making the game cheaper to duplicate and sell. Wings of Death The premise involves a wizard named Sagyr (pronounced “Sah-gear”) who seeks revenge on the evil witch Xandrilia (pronounced “Zan-drill-ear”) for transforming him into a shapeshifting winged creature, a hybrid between a dragon, wyvern, griffin, and phoenix, in addition to saving the world. To do so, he must traverse seven (7) stages which start off hard and get increasingly difficult to the point of extreme sadism. For the purpose of this review, I will cover the Amiga version using my custom-made 2-button arcade joystick. The Game This game, as is common for its era, uses multiple floppy disks, as hard disk drives were not commonplace until the Windows 95 era - in this case, it uses two (2) 3 1/2” double-density floppy diskettes, with the introduction and ending sequence on the first diskette and the second disk containing the game itself. When the game boots up, the player is greeted with the above image. Pressing any key on the keyboard or clicking the mouse will take the player to the opening credits accompanied by a very adrenaline-surging score by Jochen “Mad Max” Hippel. Pressing a button or key here will take the player to the main menu (after the player has swapped out the first disk for the second one). Each option is self-explanatory - the player can start a new game or continue a game if they run out of lives. The game is generous enough to provide the player with four (4) continues, the usage of which will take the player back to the beginning of the current level. The player can view the high scores, game information (credits) or choose between sound effects and music (the “Music+” option allows for both simultaneously, which is unusual for games from this era). Typing the word here enables a cheat mode, and the screen will flash red to confirm the correct code entry. With this cheat mode enabled, the player can do the following by pressing the respective keys on the keyboard (in parentheses): SPELLBINDER Change weapons (F1 to F5) Change power level for the current weapon (1 to 5) Change defensive powerup (F6 or F7) Activate temporary invincibility lasting approximately 20 to 30 seconds (F8) The Powerup System The game consists of a unique powerup system commonplace in most shoot-em-ups (mainly Japanese bullet hell games, from which this is indirectly inspired). The player can use between five (5) different weapons: - this is the player’s default weapon and initially fires a projectile in a straight line. Fires multiple triangular bullets at a 180-degree angle when fully upgraded. Split Fire - this fires a smaller and faster (but less powerful) projectile. Fires multiple circular bullets at a 360-degree angle (omnidirectional) when fully upgraded. Circle Blast - this is the most useful weapon in the game since it is the only weapon that has native fully automatic fire (does not require an autofire powerup) - it fires a deadly arc-shaped beam of energy in straight line and fires up to four (4) beams at various angles when fully upgraded. Power Beam - this is the most powerful weapon in the game, capable of killing most enemies in a single shot and can make quick work of bosses, defeating them in a matter of seconds - it fires a small flame and fires a pair of large jets of fire (which then split into opposite directions) when fully upgraded. Dragonfire - this is the most unconventional weapon in the game, as it is powerful but requires some trickery and expertise to master. It fires a volley of fireballs in a straight line when first picked up, and when fully upgraded, will fire a single line of fireballs which then splits into a pair of two separate volleys at right angles (90 degrees). Thunderball The player character will change shape and size to determine which powerup is currently equipped. Powerups can be upgraded by collecting an icon bearing the current powerup’s symbol, and this can be done up to four (4) times. Collecting a different powerup will not only grant the player a new weapon but will also reset the power level and necessitate collecting multiple icons of that weapon to upgrade it, so keep that in mind. The Player’s Defences No game would be fair without some form of self-defense for the player. In this case, the player has three (3) defenses available to find and collect: - this is a simple defense, orbiting the player and destroying enemies it comes into contact with - the most common defense. Destroyer - this actively seeks, locates, and destroys nearby targets in addition to enemies further away (sometimes going off-screen to do so) - less common than the Destroyer but more common than the Shield.  The Hunter and the Destroyer are mutually exclusive (picking up one will result in the loss of the other). Hunter - this grants the player temporary invincibility for about 20 or 30 seconds (the player will flash when invincible) - there is no damage recovery in this game (the player will continue taking damage for as long as they are in constant contact with an enemy or a hazard), so this defense is quite valuable, although scarce. Shield - this is the rarest of them all. It destroys all enemies currently on the screen. Smart Bomb Other Pickups - this simply adds 500 points to the player’s score. Very common and harmless. 500 Ball - this gives the player a speed boost, allowing them to move and fly faster. Wings - This pickup will nullify ALL upgrades to the player’s weapon and take away any defenses they have (including shields and speed boosts), resetting them to their initial state. Skull AVOID THIS!! - this resets the player’s health to its maximum value. Heart - this gives the player an additional life and is one of the rarest pickups in the game. Ankh - this equips the player’s current weapon with fully automatic fire. Picking up another Autofire powerup (or a different weapon) disables this. Autofire Now that the basic mechanics are covered, let’s explore the game’s levels. Stage 1: Sagyr’s Castle This level is fairly easy and gives the player ample time to get used to the game’s mechanics and difficulty. It is set in the protagonist’s castle and is populated primarily by evil statues and the occasional golden eagle, which will drop powerups when defeated. Sometimes the player will come across an entire formation of enemies - destroying the whole formation (killing every single enemy) will also drop a powerup. This stage’s hazards include fire and deadly statues and it is one of the best levels in the game. Boss: 3-headed Hydra Weakness: Head(s) Recommended Weapon: Power Beam Stage 2: The Jungle of Mutants This stage is a good showcase for what I consider to be the game’s main weakness: a gratuitous usage of vivid colors (most of the game’s stages look too garish and cartoony) resulting in the enemies and the background blending in with each other, making it difficult to evade projectiles. Natural hazards include deadly poison plants, rainbow pollen, and giant mosquitoes. About halfway through the level, the player encounters a giant ladybird which neither harms the player nor can the player harm it. This is one of the weaker levels in the game, in my opinion, due to the garish palette. Boss: Obese Beetle Weakness: Jaws Recommended Weapon: Dragonfire Stage 3: The Lethal Swamp After a brief visit into Hell for the color-deficient, we return to a much more subdued palette and environment for this third stage. This is where the difficulty begins to increment significantly after the first two levels’ somewhat easy ride. Enemies include giant floating Emperor Palpatine heads, angry mosquitoes, eccentric skeletons, and possessed swords that can attack the player from behind. Hazards include puddles and lakes of deadly bubbles. Boss: Legless Skeleton Weakness: Floating Head Recommended Weapon: Either Dragonfire or Power Beam Stage 4: A Scape of Fire The difficulty begins to increase with this stage, and the lack of health-based pickups (energy or life) does nothing to alleviate the constant projectile dodging the player will undertake for the majority of this level, which has a half-volcanic, half-Greco-Roman theme to its design. This is usually the point where even the most experienced of players will run out of their initial set of lives and get a game over, where they must choose between settling for a high score or continuing at the expense of a clean slate (their score is reset to 0 with each continue used). Hazards include pools of lava, jets of hot liquid magma, and active volcanoes complete with eruptions. Enemies include angry clouds, oversized mosquitoes, and (red gargoyle-like demons in Arab mythology). ifrits Boss: Cacodemon Weakness: Whole Body Recommended Weapon: Dragonfire Stage 5: Cold Lands of Doom and Despair As the name suggests, this stage has a very arctic theme to it. The player will be encountering all kinds of ice-themed enemies along the way, including frozen skull faces which spew fireballs and lethal possessed snowflakes. Natural hazards include Olympic torches, deadly frozen flowers which spew projectiles, and what appear to be a cross between a caterpillar and a pig in a blanket. This level does have a nice artistic touch involving frozen faces visible in the background (see the screenshot above). Boss: Angry Q*bert Lookalike Weakness: Whole Body Recommended Weapon: Dragonfire Stage 6: Crystal World This is the penultimate (second to last) stage of the game, and the difficulty is near its peak. As the name implies, the player is in a crystalline dimension. This level has very few powerups (and is full of hidden skulls), but it compensates with an abundance of shields and defenses. This time, the player can easily die due to too many sprites appearing on the screen at once and unleashing projectiles which are nearly impossible to avoid completely as opposed to the earlier stages’ garish colors. Enemies include flying skulls and angry scarabs, while natural hazards include glowing lava lamps and some of the crystals themselves. Boss: Dragon Weakness: Head Recommended Weapon: Either Dragonfire or Power Beam Stage 7 (Final Stage): Xandrilia’s Domain This is it. The last level of the game… and the difficulty is now at its apex, bordering on sadistic - this stage is a true test of the player’s skill, reflexes, and perseverance. There are enemies coming from all sides, next to no powerups, very few health-based pickups, and only a single defense and shield. The architecture is a fusion of the majestic and the infernal - this stage is full of natural hazards. Upon reaching Xandrilia’s fortress, the final boss of the game will appear in the form of a demonic dog along with possessed masks - defeat it, and you’ve won. Boss: Single-Headed Cerberus & Evil Face Masks Weakness: Head (Cerberus), Whole Body (Masks) Recommended Weapon: Either Dragonfire or Power Beam Here’s the ending sequence for those who find this game too hard or are simply too lazy to try: The ending text is transcribed here due to its questionable legibility thanks to the pseudo-medieval font used throughout the game: “Congratulations! You managed to get even with evil Xandrilia. Finally, you have regained your own form again and fame will follow you throughout her domain for the rest of your life!” Presentation The game’s presentation is very well developed and well executed for this era. The rudimentary cutscene at the end, in addition to the improvised opening credits when the game begins, does give this game a more epic scope and feel and is a sign that the developers care about their product. This is a game that was made for the 16-bit machines, and it shows, although there is a lack of optimization for the Amiga version since the Atari ST is the lead platform, which was commonplace in the era of these games. Porting aside, it is a very well-crafted effort. Graphics (Detail, Color) The game’s graphics are nicely realized and very well detailed. However, the color palette is inconsistent and can vary from level to level - this is more prominent in the early stages, where the colors used can cause enemies, hazards, and projectiles used to blend in with each other and make the game unnecessarily difficult. In the levels where the colors do have the right combination, however, every detail is vibrant and easily identifiable, and every enemy and hazard pop out at the player. The player sprites themselves are also uniquely colored, drawn, and shaped (in addition to having different sizes depending on the player’s weapon), giving the game some visual variety. Sound (SFX, Music) The game’s soundtrack is by Jochen “Mad Max” Hippel, a composer who is quite well-known on the Atari demoscene for converting SID tunes from the C64 to the Atari ST’s YM2149F chip, which is similar but not identical to the AY-3-8912 chip used in other computers of the time such as the MSX series, Amstrad CPC and 128K models of the Sinclair ZX Spectrum. As a result, the game’s soundtrack fares better on the Atari ST than on the Commodore Amiga, which utilizes mostly samples in addition to the actual recorded sound of varying quality as opposed to a series of bleeps and bloops. Sound effects are limited mostly to muffled explosions when enemies die, a voiceover announcing whatever items the player picks up, and an evil laugh that plays whenever the player loses a life or collects the dreaded skull pickup. The game does have music for nearly every setting, though - the opening credits and ending sequence have their own music, as do each of the game’s seven stages, in addition to a funky drum beat when the game loads the next level. Controls The controls are smooth and responsive - maybe a little bit too responsive, particularly when equipped with multiple speed upgrades, which could result in the player flying into enemy projectiles and/or hazards instead of trying to dodge them, which could be problematic in some of the levels with more garish color palettes, as everything just blends in together. Like most games from this era, only a single-button Atari-style joystick is supported, which is curious because, by this point, games were evolving to the point that usually overcame such a limitation, and the Atari ST and Amiga could support two (2) separate fire buttons (compatible games could use a Sega Master System/Mark 3 controller as it shares the same pinout save for an additional pin wired up to accommodate a second button) as well as the MSX computers (whose controllers were not compatible, as they were wired up slightly differently). The one complaint I do have is that the fire button must be pressed manually (and constantly) to ensure rapid fire, so this game is best played with a joystick or gamepad that supports turbo fire. I also feel that this game would have been more playable with a mouse instead of a joystick, which would have allowed a greater freedom of movement and precision. Gameplay (Difficulty, Fun-to-Frustration Ratio) The gameplay is highly reminiscent of bullet hell games, and as such, places emphasis on speed and skill, and the enemies will always appear in the same predetermined paths in the exact same sequence, eliminating any strategy from the player’s part and proving the very definition of insanity. The difficulty for the game is also a potential deterrent, as it starts off fairly challenging in the first stage and quickly becomes brutally difficult, and the final stage is the epitome of shoot-em-up gaming sadism. An option to choose the difficulty (easy, medium, or hard) would have been beneficial and could have made the game more accessible to a larger audience. The game’s strength lies in its powerups and upgrade system - the player MUST level up their weapon if they are to succeed and emerge victorious, with the Dragonfire (which can kill most enemies in less than a second) and the Power Beam (with its multiple arcs of energy at various angles) being the best weapons in the game. The weakest weapon, in my opinion, is the Circle Blast, as it does insufficient damage in its initial state, meaning enemies cannot be destroyed quickly enough to upgrade it. There is some strategy for the game’s bosses, though (the Stage 2 boss requires the player to circle around and go behind it in order to evade projectiles before coming back to the front to attack it, ditto the Stage 5 boss). Overall is a semi-classic from the peak era of 16-bit home computers, and it would not have been out of place had it originally been an arcade game. Rather than make the usual ST-to-Amiga quick port, the developers actually tried to make some use of the Amiga’s expanded capabilities, including the sampled sound and larger color palette. It sold well enough to warrant a sequel the following year (1991) in the form of (AKA ), which had a futuristic sci-fi theme and involved Sagyr fighting Xandrilia’s descendants in the far future. However, that game did not sell as well, largely due to the difficulty being even more cruel and sadistic than that of its predecessor. Wings of Death Lethal Xcess Lethal Xcess: Wings of Death 2 A lot of games made in the West (and even in Eastern Europe due to the proliferation of copies and clones made behind the Iron Curtain) ran the gauntlet from excellent to average to abominable, many of which were ported from one machine to another without optimizing the target system’s specifications and capabilities. , however, shows the potential that these machines have when coded properly and when ported with optimization in mind, rivaling some Japanese games in terms of addictiveness and atmosphere. This game is a must-have if you like a good challenge and a shooter with a unique medieval theme, regardless of whether you have an Atari ST or Commodore Amiga. Wings of Death Final Score: 4 out of 5.

Wings of Death (Commodore Amiga) Retro Game Review 

HackerNoon Reporter: Please tell us briefly about your background. My carer as a trader began in 2013. I was really excited by the stock market, and I decided to go deep into it. After two years of trading stocks and FX, I discovered options and I was very impressed by their power. What's your startup called? And in a sentence or two, what does it do? We are called LAVA, a mobile application for options trading and analyzing. We try to help our customers improve P&L and provide essential information about the stock market and options. What is the origin story? After years of trading, I realized there are plenty of solutions that help people trade options, but some of them are expensive, others too complicated. I decided to develop the best and easy tool for those who trade options, based on my experience. But I didn’t have programming experience. So, I found two people, one of them really good at coding, the other one strong in UX/UI. What do you love about your team, and why are you the ones to solve this problem? I don’t have programming experience, and I found two persons, one of them really good in coding, the other one strong in UX/UI. So we are like puzzle pieces if you put it together you will see the whole picture If you weren’t building your startup, what would you be doing? I like the financial market, and if I not making LAVA, I would be a trader. At the moment, how do you measure success? What are your core metrics? At this moment, we are at the beginning of our path, and the only metrics we have is how many downloads we have, and how many uninstall LAVA. What’s most exciting about your traction to date? The most exciting thing is that some accelerators and venture funds were looking for LAVA, and this fact gives us proof that we are in the right way. What drew you to get published on HackerNoon? What do you like most about our platform? HackerNoon is looking fresh and has an interesting audience. What advice would you give to the 21-year-old version of yourself? Work out and learn something new constantly. LAVA was nominated in Startups of the year hosted by HackerNoon. as one of the top startups in Moscow

Startup Interview with Denis Vasilev, LAVA's Founder

Written by Dr. Vincent Gramoli (Data61-CSIRO, University of Sydney) Consensus is a fundamental problem of distributed computing. While this problem has been known to be unsolvable, existing protocols were designed to solve consensus under various assumptions. Today, with the recent advent of blockchains, various consensus implementations were proposed to make replicas reach an agreement on the order of transactions that update the distributed ledger. However, very little work has been devoted to assessing their security level. As a result, existing protocols are sometimes misunderstood and it is often unclear whether the problems arising during their executions are due to implementation bugs or more fundamental design issues. The proof-of-work blockchains, like Bitcoin and Ethereum, have been shown both theoretically and empirically vulnerable to double spending attacks. In one my research papers “ I already discussed the mainstream blockchain consensus algorithms and warned about the dangers of using these blockchains without understanding precisely the guarantees their consensus algorithm offers. From Blockchain Consensus Back to Byzantine Consensus ” Ethereum is one of the most popular open blockchain systems thanks to the large ecosystem of distributed applications that it executes. But unfortunately, the default Ethereum protocol, called proof-of-work (PoW), is forkable because it allows distinct blocks to be appended at the same index of the chain. A fork can lead to security vulnerabilities, like double spending, when growing without being noticed. As a result, the trend seems to reuse Byzantine fault tolerance in a new class of protocols called proof-of-authority (PoA), that aims at avoiding double spending , that has recently been integrated into the most deployed Ethereum clients, and and is used by industries. parity geth, These Ethereum consensus algorithms, called Aura and Clique, are said to implement PoA because they restrict the creation of a block to a fixed set of authority nodes, called sealers. They aim at solving the well-known Byzantine consensus problem, where a fixed set of nodes agree on a unique block despite the presence of Byzantine nodes. PoA gives the sealers the authority to seal a block, which consists of signing cryptographically the block. This set of sealers can possibly change over time if a subset of the participants allows it, similarly to what is known as community blockchains. This PoA is an appealing alternative to PoW for industries that are not interested in spending a large amount of CPU resources in exchange of a reward expressed in a cryptocurrency but are more interested in avoiding forks to increase security. For these reasons, PoA recently got traction in the industry. . Industrials, like Lavaa, propose a tracking service to prevent fraud counterfeiting, that was experimented on Ethereum/Aura. They implemented a service that aims at maintaining data privacy and integrity in a multi-tenant scenario. . They suggest Azure customers to deploy the Aura protocol across different regions to improve the availability of the service. Amazon Web Services offers PoA through the Clique protocol built in geth to its customers Microsoft describes how to deploy Ethereum/Aura “in production” However, the level of security offered by PoA protocols has not been assessed yet and it has been unclear whether an attacker could violate data integrity. As the industry is building upon these protocols to use Ethereum in a consortium of institutions, it has become crucial to assess their vulnerability. In a new paper ”, written in collaboration with colleague researchers from University of Sydney and CSIRO, we explored vulnerabilities and countermeasures of the PoA consensus protocol. “The Attack of the Clones Against Proof-of-Authority In the paper, we showed that, under specific conditions, PoA is not secure. We designed, implemented and experimented an attack, called the Cloning Attack, against both Ethereum/Aura and the Ethereum/Clique protocols that allowed to steal digital assets and proposed ways to alleviate the vulnerability. We deployed both versions of PoA Ethereum on our private testnet and performed the Cloning Attack on both protocols. On the one hand, we found that Aura required lesser topological knowledge for a malicious sealer to achieve double spending with 100% success rate when compared to Clique. On the other hand, the attack against Clique is about twice faster but its success rate ranges from 60% to 100% depending on the topology knowledge of malicious sealers. As, a result it appears that, despite its recently introduced Byzantine fault tolerance, Ethereum remains highly vulnerable to networking attacks when used in a consortium. In order to remedy this vulnerability, we proposed to modify these two consensus algorithms and preserve their safety guarantees. However, as a drawback, our counter-measures introduce some potential limitation to the liveness of the Clique algorithm. As a counter-measure we propose a particularly promising protocol — the . It relies on the Democratic BFT that solves the Blockchain Byzantine Consensus problem. Because it does not rely on an off-the-shelf classic Byzantine consensus algorithm, the Red Belly Blockchain already scales to more than 100 consensus participants and handles a workload of more than 600 thousand transactions per second, hence tolerating a potentially much larger number of blockchain participants issuing transactions and requesting balances than other blockchains. In contrast with other large-scale blockchains, the Red Belly Blockchain achieves fast settlement (typically within 3 seconds) because it does not need any proof-of-work. Red Belly Blockchain The paper “The Attack of the Clones Against Proof-of-Authority” was written by Dr. Vincent Gramoli (University of Sydney), Parinya Ekparinya (University of Sydney) and Guillaume Jourjon (Data61-CSIRO) and can be found under the following link: https://www.researchgate.net/publication/331370565_The_Attack_of_the_Clones_Against_Proof-of-Authority Dr. Vincent Gramoli is an Associate Professor at the University of Sydney where he leads the Concurrent Systems Research Group. He is also a senior researcher at Data61-CSIRO. Prior to this, he was affiliated with INRIA, Cornell and EPFL. Vincent is the Chair of the Blockchain Technical Committee at the Australian Computer Society and a Future Fellow of the Australian Research Council.

Are Bitcoin And Ethereum As Secure As You Think?

Cryptography can be used to have not only decentralized and private money but also private communications. The activists known as cypherpunks knew this too well, and that’s why not only Bitcoin came out from that mailing list started in the ’90s. A bunch of free and useful cryptographic tools are the legacy of cypherpunks, including the one created by Phil Zimmerman —a remarkable cypherpunk even to this day. Born on February 12, 1954, in Camden, New Jersey, Zimmermann studied computer science at Florida Atlantic University, where he earned his degree in 1978. His career trajectory began with software engineering roles in various companies, including a stint at the nuclear power company, System Simulation Corporation, where he worked on cryptographic security systems. However, the interesting part is that he was also an anti-nuclear activist. It’s known that he was arrested for partaking in an anti-nuclear protest in Nevada, alongside prominent figures like Carl Sagan and Martin Sheen. This commitment to activism underscored Zimmermann's convictions, solidifying his standing within the anti-nuclear movement. Amidst the shifting geopolitical landscape of the early 1990s, Zimmermann's focus pivoted towards cryptography, recognizing its potential to safeguard private communications in an increasingly interconnected world. It was during this period that he would join the cypherpunks and create his ‘magnum opus’. Pretty Good Privacy (PGP) This is a thing even Satoshi Nakamoto used to protect his emails, and it’s still widely used as a standard to achieve private communications. Developed in 1991, PGP is an encryption software designed to secure email messages. Zimmermann's motivation behind PGP was rooted in his concerns about government surveillance and the need for accessible cryptographic tools to protect individual privacy. In his own words: “It's personal. It's private. And it's no one's business but yours. You may be planning a political campaign, discussing your taxes, or having a secret romance. Or you may be communicating with a political dissident in a repressive country. Whatever it is, you don't want your private electronic mail (email) or confidential documents read by anyone else (...) PGP empowers people to take their privacy into their own hands. There has been a growing social need for it. That's why I wrote it.” As for its internal features, PGP uses a pair of cryptographic keys for each user—a public key and a private key. The public key, which is freely distributed, is used by others to encrypt messages intended for the user. Meanwhile, the private key, kept confidential by the user, is used for decrypting these messages. When someone wants to send an encrypted message to a PGP user, they obtain the recipient's public key. Using this key, they encrypt the message, ensuring that only the intended recipient, who possesses the corresponding private key, can decrypt and read it. This process provides confidentiality for the message. Additionally, PGP supports digital signatures, enabling users to verify the authenticity and integrity of emails. By hashing the message and encrypting the hash with their private key, senders create digital signatures that recipients can verify using the sender's public key. After PGP Back then, the US government considered cryptographic tools as weapons, and that’s why Zimmerman was investigated by authorities for the free distribution of PGP. Luckily, they dropped the case in 1996 without charges, and the cypherpunk founded PGP Inc., along with a new release of PGP. The company in charge of maintaining the software was eventually sold to Symantec in 2010. Following the success of PGP, Zimmermann has also been involved in various ventures aimed at bolstering digital security and privacy. In 2012, he co-founded Silent Circle alongside Mike Janke and Jon Callas, focusing on developing secure hardware and subscription-based software solutions. Additionally, Zimmermann collaborated with other key figures from Silent Circle and Lavabit (an encrypted webmail service) to establish the Dark Mail Alliance in 2013, with the objective of creating a new protocol to enhance email encryption, addressing limitations in PGP. Beyond his cryptographic endeavors, Zimmermann extended his influence to social networking platforms, advocating for ethical and privacy-centric alternatives to mainstream platforms like Facebook. His involvement in the social network Okuna, previously known as Openbook, aimed to provide users with a platform that prioritized privacy and democratic values over profit-driven models. Zimmermann's contributions have been widely recognized, with numerous awards acknowledging his pioneering work in cryptography and advocacy for digital rights. From inductions into halls of fame to prestigious accolades such as the Louis Brandeis Award from Privacy International and the Norbert Wiener Award for Social and Professional Responsibility, Zimmermann's legacy continues to resonate within the realms of technology and human rights advocacy. In a world of surveillance There’s a thing called “the Zimmerman law” that refers to his words about technology and surveillance: “The natural flow of technology tends to move in the direction of making surveillance easier (…) the ability of computers to track us doubles every eighteen months.” If the period is exact or not in reality, it doesn’t matter, because today mass surveillance and censorship have become common feats by governments worldwide. PGP can help us to protect our privacy and digital rights, but it’s not the only tool available for that. Obyte, for instance, can also help with private communications and decentralized, fast, and secure financial transactions worldwide. Built on a Directed Acyclic Graph (DAG) structure, Obyte ensures global transactions without the need for miners or any other middlemen. This structure enables Obyte to increase its decentralization and offers a high level of control to its users. In addition to its financial features, where tokenization of any asset is also possible, Obyte integrates private communications functionality directly into its platform. Users can leverage Obyte's built-in messaging system in the wallet to communicate securely and privately, thanks to end-to-end encryption, similar to PGP. This feature enhances user privacy by enabling them to freely communicate without a company or government behind them, thus providing a comprehensive solution for both financial transactions and private messaging. As a result, we can say that Obyte is empowering users with a versatile platform for conducting secure and private interactions worldwide. Read more from Cypherpunks Write Code series: Tim May & Crypto-anarchism Wei Dai & B-money Nick Szabo & Smart Contracts Adam Back & Hashcash Eric Hughes & Remailer St Jude & Community Memory Hal Finney & RPOW Featured Vector Image by Garry Killian / Freepik Photo by Phil Zimmerman Cryptography can be used to have not only decentralized and private money but also private communications. The activists known as cypherpunks knew this too well, and that’s why not only Bitcoin came out from that mailing list started in the ’90s. A bunch of free and useful cryptographic tools are the legacy of cypherpunks, including the one created by Phil Zimmerman —a remarkable cypherpunk even to this day. that mailing list that mailing list Born on February 12, 1954, in Camden, New Jersey, Zimmermann studied computer science at Florida Atlantic University, where he earned his degree in 1978. His career trajectory began with software engineering roles in various companies, including a stint at the nuclear power company, System Simulation Corporation, where he worked on cryptographic security systems. Zimmermann studied computer science at Florida Atlantic University, where he earned his degree in 1978. Zimmermann Zimmermann However, the interesting part is that he was also an anti-nuclear activist. It’s known that he was arrested for partaking in an anti-nuclear protest in Nevada, alongside prominent figures like Carl Sagan and Martin Sheen. This commitment to activism underscored Zimmermann's convictions, solidifying his standing within the anti-nuclear movement. It’s known It’s known Amidst the shifting geopolitical landscape of the early 1990s, Zimmermann's focus pivoted towards cryptography, recognizing its potential to safeguard private communications in an increasingly interconnected world. It was during this period that he would join the cypherpunks and create his ‘magnum opus’. Pretty Good Privacy (PGP) This is a thing even Satoshi Nakamoto used to protect his emails, and it’s still widely used as a standard to achieve private communications. Developed in 1991, PGP is an encryption software designed to secure email messages . Zimmermann's motivation behind PGP was rooted in his concerns about government surveillance and the need for accessible cryptographic tools to protect individual privacy. In his own words : Developed in 1991, PGP is an encryption software designed to secure email messages In his own words In his own words “It's personal. It's private. And it's no one's business but yours. You may be planning a political campaign, discussing your taxes, or having a secret romance. Or you may be communicating with a political dissident in a repressive country. Whatever it is, you don't want your private electronic mail (email) or confidential documents read by anyone else (...) PGP empowers people to take their privacy into their own hands. There has been a growing social need for it. That's why I wrote it.” “It's personal. It's private. And it's no one's business but yours. You may be planning a political campaign, discussing your taxes, or having a secret romance. Or you may be communicating with a political dissident in a repressive country. Whatever it is, you don't want your private electronic mail (email) or confidential documents read by anyone else (...) PGP empowers people to take their privacy into their own hands. There has been a growing social need for it. That's why I wrote it.” As for its internal features, PGP uses a pair of cryptographic keys for each user—a public key and a private key. The public key, which is freely distributed, is used by others to encrypt messages intended for the user. Meanwhile, the private key, kept confidential by the user, is used for decrypting these messages. When someone wants to send an encrypted message to a PGP user, they obtain the recipient's public key. Using this key, they encrypt the message, ensuring that only the intended recipient, who possesses the corresponding private key, can decrypt and read it. This process provides confidentiality for the message. Additionally, PGP supports digital signatures, enabling users to verify the authenticity and integrity of emails. By hashing the message and encrypting the hash with their private key, senders create digital signatures that recipients can verify using the sender's public key. After PGP After PGP Back then, the US government considered cryptographic tools as weapons, and that’s why Zimmerman was investigated by authorities for the free distribution of PGP. Luckily, they dropped the case in 1996 without charges, and the cypherpunk founded PGP Inc., along with a new release of PGP. The company in charge of maintaining the software was eventually sold to Symantec in 2010. Following the success of PGP, Zimmermann has also been involved in various ventures aimed at bolstering digital security and privacy. In 2012, he co-founded Silent Circle alongside Mike Janke and Jon Callas, focusing on developing secure hardware and subscription-based software solutions. Additionally, Zimmermann collaborated with other key figures from Silent Circle and Lavabit (an encrypted webmail service) to establish the Dark Mail Alliance in 2013, with the objective of creating a new protocol to enhance email encryption, addressing limitations in PGP. Following the success of PGP, Zimmermann has also been involved in various ventures aimed at bolstering digital security and privacy. Beyond his cryptographic endeavors, Zimmermann extended his influence to social networking platforms, advocating for ethical and privacy-centric alternatives to mainstream platforms like Facebook. His involvement in the social network Okuna , previously known as Openbook, aimed to provide users with a platform that prioritized privacy and democratic values over profit-driven models. Okuna Okuna Zimmermann's contributions have been widely recognized, with numerous awards acknowledging his pioneering work in cryptography and advocacy for digital rights. From inductions into halls of fame to prestigious accolades such as the Louis Brandeis Award from Privacy International and the Norbert Wiener Award for Social and Professional Responsibility, Zimmermann's legacy continues to resonate within the realms of technology and human rights advocacy. In a world of surveillance In a world of surveillance There’s a thing called “the Zimmerman law” that refers to his words about technology and surveillance: “The natural flow of technology tends to move in the direction of making surveillance easier (…) the ability of computers to track us doubles every eighteen months.” If the period is exact or not in reality, it doesn’t matter, because today mass surveillance and censorship have become common feats by governments worldwide. his words his words “The natural flow of technology tends to move in the direction of making surveillance easier (…) the ability of computers to track us doubles every eighteen months.” mass surveillance mass surveillance PGP can help us to protect our privacy and digital rights, but it’s not the only tool available for that. Obyte , for instance, can also help with private communications and decentralized, fast, and secure financial transactions worldwide. Built on a Directed Acyclic Graph (DAG) structure, Obyte ensures global transactions without the need for miners or any other middlemen. This structure enables Obyte to increase its decentralization and offers a high level of control to its users. Obyte Obyte In addition to its financial features, where tokenization of any asset is also possible, Obyte integrates private communications functionality directly into its platform. Users can leverage Obyte's built-in messaging system in the wallet to communicate securely and privately, thanks to end-to-end encryption, similar to PGP. tokenization of any asset tokenization of any asset in the wallet in the wallet This feature enhances user privacy by enabling them to freely communicate without a company or government behind them, thus providing a comprehensive solution for both financial transactions and private messaging. As a result, we can say that Obyte is empowering users with a versatile platform for conducting secure and private interactions worldwide. Read more from Cypherpunks Write Code series: Read more from Cypherpunks Write Code series: Read more from Cypherpunks Write Code series: Tim May & Crypto-anarchism Tim May & Crypto-anarchism Tim May & Crypto-anarchism Wei Dai & B-money Wei Dai & B-money Wei Dai & B-money Nick Szabo & Smart Contracts Nick Szabo & Smart Contracts Nick Szabo & Smart Contracts Adam Back & Hashcash Adam Back & Hashcash Adam Back & Hashcash Eric Hughes & Remailer Eric Hughes & Remailer Eric Hughes & Remailer St Jude & Community Memory St Jude & Community Memory St Jude & Community Memory Hal Finney & RPOW Hal Finney & RPOW Hal Finney & RPOW Featured Vector Image by Garry Killian / Freepik Featured Vector Image by Garry Killian / Freepik Freepik Freepik Photo by Phil Zimmerman Photo by Phil Zimmerman Phil Zimmerman Phil Zimmerman

Cypherpunks Write Code: Phil Zimmerman and PGP

সাইফারপাঙ্কস কোড লিখুন: ফিল জিমারম্যান এবং পিজিপি

Cypherpunks schreiben Code: Phil Zimmerman und PGP

Código de escritura de Cypherpunks: Phil Zimmerman y PGP

Cypherpunks écrivent du code : Phil Zimmerman et PGP

साइफरपंक्स कोड लिखें: फिल ज़िमरमैन और पीजीपी

サイファーパンクがコードを書く: フィル・ジマーマンと PGP

사이퍼펑크의 코드 작성: Phil Zimmerman 및 PGP

Cypherpunks escrevem código: Phil Zimmerman e PGP

Шифропанки пишут код: Фил Циммерман и PGP

Şifrepunklar Kod Yazıyor: Phil Zimmerman ve PGP

Cypherpunks viết mã: Phil Zimmerman và PGP

密码朋克编写代码：Phil Zimmerman 和 PGP

Authors:
(1) Aya Kherrour, Department of Information Engineering and Computer Science University of Trento;
(2) Marco Robol, Department of Information Engineering and Computer Science University of Trento;
(3) Marco Roveri, Department of Information Engineering and Computer Science University of Trento;
(4) Paolo Giorgini, Department of Information Engineering and Computer Science University of Trento. 6 Conclusion This work aimed to evaluate the performance of several known heuristic search algorithms, such as D*, D* Lite, LPA*, LRTA*, RTAA*, and ARA* in terms of solving time, memory consumption, and path cost. The evaluation was made using different randomly generated grid environments with different characteristics alongside personalized grid environments with horizontal walls and different wall lengths as different hinders. Our experimental evaluation revealed that all the algorithms exhibit different performances with strengths and weaknesses under different grid characterizations. D* Lite consistently generated the shortest paths even in obstacle-dense grids, indicating its efficiency in dense environments. ARA* consistently provides faster solutions as the grid size increases, particularly larger than 100, while RTTA* generates faster solutions in smaller grid sizes, with the advantage of not being affected by dense environments. Our study provides valuable insights into selecting the appropriate heuristic search algorithm in the pathfinding domain. Using these insights, we propose a selection algorithm used to optimize the performance needed in a pathfinding domain, such as, solving time, path length, or memory consumption. However, our evaluation focused only on static environments, while dynamic environments may introduce additional challenges. Furthermore, we considered a limited set of experiments, not covering all possible combinations of the grid characteristics. This limitation means that the selection algorithm might not always recommend the most optimal solution, as seen in the example we introduced to evaluate our algorithm. In future work, we aim to address these limitations as follows: Firstly, we plan to extend our evaluation of the search algorithms to include dynamic environments. Secondly, we intend to explore various combinations of both domain characterization and priorities. Furthermore, we want to include additional scenario configuration, extending the random obstacles and the walls scenarios. With such additional understanding, we aim to refine our selection algorithm to automatically take decisions among the best search algorithms, based on the type of obstacles in the local search space. References [1] Nafiz Arica, Aysegul Mut, Alper Yörükçü & Kadir Alpaslan Demir (2017): An Empirical Comparison of Search Approaches for Moving Agents. Comput. Intell. 33(3), pp. 368–400, doi:10.1111/coin.12092. [2] Yngvi Björnsson, Vadim Bulitko & Nathan R. Sturtevant (2009): TBA*: Time-Bounded A*. In Craig Boutilier, editor: IJCAI 2009, Proceedings of the 21st International Joint Conference on Artificial Intelligence, Pasadena, California, USA, July 11-17, 2009, pp. 431–436. Available at http://ijcai.org/ Proceedings/09/Papers/079.pdf. [3] David Bond, Niels A. Widger, Wheeler Ruml & Xiaoxun Sun (2010): Real-Time Search in Dynamic Worlds. In Ariel Felner & Nathan R. Sturtevant, editors: Proceedings of the Third Annual Symposium on Combinatorial Search, SOCS 2010, Stone Mountain, Atlanta, Georgia, USA, July 8 10, 2010, AAAI Press, doi:10.1609/socs.v1i1.18174. Available at http://aaai.org/ocs/index.php/SOCS/SOCS10/paper/ view/2103. [4] Guillaume Brat, Ewen Denney, Dimitra Giannakopoulou, Jeremy Frank & Ari Jónsson (2006): Verification of autonomous systems for space applications. In: 2006 IEEE Aerospace Conference, IEEE, pp. 11–pp, doi:10.1109/AERO.2006.1656029. [5] Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest & Clifford Stein (2009): Introduction to Algorithms, 3rd Edition. MIT Press. Available at http://mitpress.mit.edu/books/ introduction-algorithms. [6] A. Elfes (1989): Using occupancy grids for mobile robot perception and navigation. Computer 22(6), pp. 46–57, doi:10.1109/2.30720. [7] Carlos Hernández & Jorge A. Baier (2011): Real-Time Heuristic Search with Depression Avoidance. In Toby Walsh, editor: IJCAI 2011, Proceedings of the 22nd International Joint Conference on Artificial Intelligence, Barcelona, Catalonia, Spain, July 16-22, 2011, IJCAI/AAAI, pp. 578–583, doi:10.5591/978-1-57735-516- 8/IJCAI11-104. [8] Mohd Javaid, Abid Haleem, Ravi Pratap Singh & Rajiv Suman (2021): Substantial capabilities of robotics in enhancing industry 4.0 implementation. Cognitive Robotics 1, pp. 58–75, doi:10.1016/j.cogr.2021.06.001. [9] Sven Koenig (2001): Agent-Centered Search. AI Mag. 22(4), pp. 109–132, doi:10.1609/aimag.v22i4.1596. [10] Sven Koenig (2004): A Comparison of Fast Search Methods for Real-Time Situated Agents, pp. 864–871. doi:10.1109/AAMAS.2004.10122. Available at https://doi.ieeecomputersociety.org/10.1109/ AAMAS.2004.10122. [11] Sven Koenig & Maxim Likhachev (2002): D*Lite, pp. 476–483. Available at http://www.aaai.org/ Library/AAAI/2002/aaai02-072.php. [12] Sven Koenig & Maxim Likhachev (2006): Real-time adaptive A*. In Hideyuki Nakashima, Michael P. Wellman, Gerhard Weiss & Peter Stone, editors: 5th International Joint Conference on Autonomous Agents and Multiagent Systems (AAMAS 2006), Hakodate, Japan, May 8-12, 2006, ACM, pp. 281–288, doi:10.1145/1160633.1160682. [13] Sven Koenig & Xiaoxun Sun (2009): Comparing real-time and incremental heuristic search for real-time situated agents. Auton. Agents Multi Agent Syst. 18(3), pp. 313–341, doi:10.1007/s10458 008-9061-x. [14] Richard E Korf (1990): Real-time heuristic search. Artificial intelligence 42(2-3), pp. 189–211, doi:10.1016/0004-3702(90)90054-4. [15] Maxim Likhachev, Geoffrey J. Gordon & Sebastian Thrun (2003): ARA*: Anytime A* with Provable Bounds on Sub-Optimality, pp. 767–774. Available at https://proceedings.neurips.cc/paper/2003/hash/ ee8fe9093fbbb687bef15a38facc44d2-Abstract.html. [16] Manuel Müller, Timo Müller, Behrang Ashtari Talkhestani, Philipp Marks, Nasser Jazdi & Michael Weyrich (2021): Industrial autonomous systems: a survey on definitions, characteristics and abilities. atAutomatisierungstechnik 69(1), pp. 3–13, doi:10.1515/auto-2020-0131. [17] Michal Pechoucek, Simon G Thompson & Holger Voos (2008): Defence Industry Applications of Autonomous Agents and Multi-Agent Systems. Springer, doi:10.1007/978-3-7643-8571-2. [18] Francisco J Perez-Grau, J Ramiro Martinez-de Dios, Julio L Paneque, J Joaquin Acevedo, Arturo Torres-González, Antidio Viguria, Juan R Astorga & Anibal Ollero (2021): Introducing autonomous aerial robots in industrial manufacturing. Journal of Manufacturing Systems 60, pp. 312–324, doi:10.1016/j.jmsy.2021.06.008. [19] José Ricardo Sánchez-Ibáñez, Carlos Jesús Pérez-del-Pulgar & Alfonso García-Cerezo (2021): Path Planning for Autonomous Mobile Robots: A Review. Sensors 21(23), p. 7898, doi:10.3390/s21237898. [20] Anthony Stentz (1995): The Focussed D* Algorithm for Real-Time Replanning. In: Proceedings of the Fourteenth International Joint Conference on Artificial Intelligence, IJCAI 95, Montréal Québec, Canada, August 20-25 1995, 2 Volumes, Morgan Kaufmann, pp. 1652–1659. Available at http://ijcai.org/ Proceedings/95-2/Papers/082.pdf. [21] Dmitry S. Yershov & Steven M. LaValle (2011): Simplicial Dijkstra and A* algorithms for optimal feedback planning. In: 2011 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2011, San Francisco, CA, USA, September 25-30, 2011, IEEE, pp. 3862–3867, doi:10.1109/IROS.2011.6095032. This paper is available on arxiv under CC 4.0 license. Authors: (1) Aya Kherrour, Department of Information Engineering and Computer Science University of Trento; (2) Marco Robol, Department of Information Engineering and Computer Science University of Trento; (3) Marco Roveri, Department of Information Engineering and Computer Science University of Trento; (4) Paolo Giorgini, Department of Information Engineering and Computer Science University of Trento. Authors: (1) Aya Kherrour, Department of Information Engineering and Computer Science University of Trento; (2) Marco Robol, Department of Information Engineering and Computer Science University of Trento; (3) Marco Roveri, Department of Information Engineering and Computer Science University of Trento; (4) Paolo Giorgini, Department of Information Engineering and Computer Science University of Trento. 6 Conclusion This work aimed to evaluate the performance of several known heuristic search algorithms, such as D*, D* Lite, LPA*, LRTA*, RTAA*, and ARA* in terms of solving time, memory consumption, and path cost. The evaluation was made using different randomly generated grid environments with different characteristics alongside personalized grid environments with horizontal walls and different wall lengths as different hinders. Our experimental evaluation revealed that all the algorithms exhibit different performances with strengths and weaknesses under different grid characterizations. D* Lite consistently generated the shortest paths even in obstacle-dense grids, indicating its efficiency in dense environments. ARA* consistently provides faster solutions as the grid size increases, particularly larger than 100, while RTTA* generates faster solutions in smaller grid sizes, with the advantage of not being affected by dense environments. Our study provides valuable insights into selecting the appropriate heuristic search algorithm in the pathfinding domain. Using these insights, we propose a selection algorithm used to optimize the performance needed in a pathfinding domain, such as, solving time, path length, or memory consumption. However, our evaluation focused only on static environments, while dynamic environments may introduce additional challenges. Furthermore, we considered a limited set of experiments, not covering all possible combinations of the grid characteristics. This limitation means that the selection algorithm might not always recommend the most optimal solution, as seen in the example we introduced to evaluate our algorithm. In future work, we aim to address these limitations as follows: Firstly, we plan to extend our evaluation of the search algorithms to include dynamic environments. Secondly, we intend to explore various combinations of both domain characterization and priorities. Furthermore, we want to include additional scenario configuration, extending the random obstacles and the walls scenarios. With such additional understanding, we aim to refine our selection algorithm to automatically take decisions among the best search algorithms, based on the type of obstacles in the local search space. References [1] Nafiz Arica, Aysegul Mut, Alper Yörükçü & Kadir Alpaslan Demir (2017): An Empirical Comparison of Search Approaches for Moving Agents. Comput. Intell. 33(3), pp. 368–400, doi:10.1111/coin.12092. [2] Yngvi Björnsson, Vadim Bulitko & Nathan R. Sturtevant (2009): TBA*: Time-Bounded A*. In Craig Boutilier, editor: IJCAI 2009, Proceedings of the 21st International Joint Conference on Artificial Intelligence, Pasadena, California, USA, July 11-17, 2009, pp. 431–436. Available at http://ijcai.org/ Proceedings/09/Papers/079.pdf. [3] David Bond, Niels A. Widger, Wheeler Ruml & Xiaoxun Sun (2010): Real-Time Search in Dynamic Worlds. In Ariel Felner & Nathan R. Sturtevant, editors: Proceedings of the Third Annual Symposium on Combinatorial Search, SOCS 2010, Stone Mountain, Atlanta, Georgia, USA, July 8 10, 2010, AAAI Press, doi:10.1609/socs.v1i1.18174. Available at http://aaai.org/ocs/index.php/SOCS/SOCS10/paper/ view/2103. [4] Guillaume Brat, Ewen Denney, Dimitra Giannakopoulou, Jeremy Frank & Ari Jónsson (2006): Verification of autonomous systems for space applications. In: 2006 IEEE Aerospace Conference, IEEE, pp. 11–pp, doi:10.1109/AERO.2006.1656029. [5] Thomas H. Cormen, Charles E. Leiserson, Ronald L. Rivest & Clifford Stein (2009): Introduction to Algorithms, 3rd Edition. MIT Press. Available at http://mitpress.mit.edu/books/ introduction-algorithms. [6] A. Elfes (1989): Using occupancy grids for mobile robot perception and navigation. Computer 22(6), pp. 46–57, doi:10.1109/2.30720. [7] Carlos Hernández & Jorge A. Baier (2011): Real-Time Heuristic Search with Depression Avoidance. In Toby Walsh, editor: IJCAI 2011, Proceedings of the 22nd International Joint Conference on Artificial Intelligence, Barcelona, Catalonia, Spain, July 16-22, 2011, IJCAI/AAAI, pp. 578–583, doi:10.5591/978-1-57735-516- 8/IJCAI11-104. [8] Mohd Javaid, Abid Haleem, Ravi Pratap Singh & Rajiv Suman (2021): Substantial capabilities of robotics in enhancing industry 4.0 implementation. Cognitive Robotics 1, pp. 58–75, doi:10.1016/j.cogr.2021.06.001. [9] Sven Koenig (2001): Agent-Centered Search. AI Mag. 22(4), pp. 109–132, doi:10.1609/aimag.v22i4.1596. [10] Sven Koenig (2004): A Comparison of Fast Search Methods for Real-Time Situated Agents, pp. 864–871. doi:10.1109/AAMAS.2004.10122. Available at https://doi.ieeecomputersociety.org/10.1109/ AAMAS.2004.10122. [11] Sven Koenig & Maxim Likhachev (2002): D*Lite, pp. 476–483. Available at http://www.aaai.org/ Library/AAAI/2002/aaai02-072.php. [12] Sven Koenig & Maxim Likhachev (2006): Real-time adaptive A*. In Hideyuki Nakashima, Michael P. Wellman, Gerhard Weiss & Peter Stone, editors: 5th International Joint Conference on Autonomous Agents and Multiagent Systems (AAMAS 2006), Hakodate, Japan, May 8-12, 2006, ACM, pp. 281–288, doi:10.1145/1160633.1160682. [13] Sven Koenig & Xiaoxun Sun (2009): Comparing real-time and incremental heuristic search for real-time situated agents. Auton. Agents Multi Agent Syst. 18(3), pp. 313–341, doi:10.1007/s10458 008-9061-x. [14] Richard E Korf (1990): Real-time heuristic search. Artificial intelligence 42(2-3), pp. 189–211, doi:10.1016/0004-3702(90)90054-4. [15] Maxim Likhachev, Geoffrey J. Gordon & Sebastian Thrun (2003): ARA*: Anytime A* with Provable Bounds on Sub-Optimality, pp. 767–774. Available at https://proceedings.neurips.cc/paper/2003/hash/ ee8fe9093fbbb687bef15a38facc44d2-Abstract.html. [16] Manuel Müller, Timo Müller, Behrang Ashtari Talkhestani, Philipp Marks, Nasser Jazdi & Michael Weyrich (2021): Industrial autonomous systems: a survey on definitions, characteristics and abilities. atAutomatisierungstechnik 69(1), pp. 3–13, doi:10.1515/auto-2020-0131. [17] Michal Pechoucek, Simon G Thompson & Holger Voos (2008): Defence Industry Applications of Autonomous Agents and Multi-Agent Systems. Springer, doi:10.1007/978-3-7643-8571-2. [18] Francisco J Perez-Grau, J Ramiro Martinez-de Dios, Julio L Paneque, J Joaquin Acevedo, Arturo Torres-González, Antidio Viguria, Juan R Astorga & Anibal Ollero (2021): Introducing autonomous aerial robots in industrial manufacturing. Journal of Manufacturing Systems 60, pp. 312–324, doi:10.1016/j.jmsy.2021.06.008. [19] José Ricardo Sánchez-Ibáñez, Carlos Jesús Pérez-del-Pulgar & Alfonso García-Cerezo (2021): Path Planning for Autonomous Mobile Robots: A Review. Sensors 21(23), p. 7898, doi:10.3390/s21237898. [20] Anthony Stentz (1995): The Focussed D* Algorithm for Real-Time Replanning. In: Proceedings of the Fourteenth International Joint Conference on Artificial Intelligence, IJCAI 95, Montréal Québec, Canada, August 20-25 1995, 2 Volumes, Morgan Kaufmann, pp. 1652–1659. Available at http://ijcai.org/ Proceedings/95-2/Papers/082.pdf. [21] Dmitry S. Yershov & Steven M. LaValle (2011): Simplicial Dijkstra and A* algorithms for optimal feedback planning. In: 2011 IEEE/RSJ International Conference on Intelligent Robots and Systems, IROS 2011, San Francisco, CA, USA, September 25-30, 2011, IEEE, pp. 3862–3867, doi:10.1109/IROS.2011.6095032. This paper is available on arxiv under CC 4.0 license. This paper is available on arxiv under CC 4.0 license. available on arxiv

Future Directions in Heuristic Search

Transcendence Book 9: Far-skies

Systems Interoperability Types: The Conclusion to Our Tertiary Study

Author(s): (1) Gopal Yadav, Department of Physics, Indian Institute of Technology & Chennai Mathematical Institute. Table of Links Abstract & Introduction Brief Review of Wedge Holography Emerging Multiverse from Wedge Holography Application to Information Paradox Application to Grandfather Paradox Conclusion Acknowledgements and References Acknowledgements The author is supported by a Senior Research Fellowship (SRF) from the Council of Scientific and Industrial Research (CSIR), Govt. of India. It is my pleasure to thank Aalok Misra, who motivated me to work on the entanglement stuff, and for his blessings. We would also like to thank Juan Maldacena, Andreas Karch, Kostas Skenderis and Tadashi Takayanagi for very helpful discussions and comments. This research was also supported in part by the International Centre for Theoretical Sciences (ICTS) for the program “Nonperturbative and Numerical Approaches to Quantum Gravity, String Theory and Holography” (code:ICTS/numstrings-2022/8). 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Multiverse in Karch-Randall Braneworld: Acknowledgements and References

Aspects of Thermal QCD Phenomenology at Intermediate Gauge/'t Hooft Coupling: Bibliography

Overview According to statistics, there were 21 funding rounds executed in the global blockchain market from February 12 to February 18, totaling 137 million dollars. The number of funding rounds increased by 1, and the amount of funds increased by 30.47% compared with the previous week. The number of funding rounds in the infrastructure and DeFi sectors is the highest, 7 of which are in the infrastructure sector and 4 in the DeFi area. The funds raised in the infrastructure sector are the highest, which is 46.5 million dollars. Funding in different sectors Infrastructure Analog Round / Amount $16M Investors NGC Ventures, Tribe Capital, Alumni Ventures Analog is a completely decentralized layer-0 platform for communicating validated event data with the Proof-of-Time consensus mechanism. At the core of the platform are tesseracts and time nodes that can privately fetch and confirm event data from sovereign chains, allowing different ecosystems to speak the same language. Analog aims to bring trustless, omnichain interoperability, enabling developers to build their applications via a universal protocol and an API. Additionally, Analog is unveiling a novel, superfast PoT protocol that creates verifiable event data on the Timechain, allowing DApp developers to build next-generation event-based applications. Project Intro: The testnet is now live! Enter your email to join the waiting list, and we already have nearly 100,000 reservations. In this phase, we've introduced a point system where you can accumulate Spot by completing tasks such as following Twitter, joining the community, and more. After registering, head to the Web3 platform TaskOn to complete tasks and participate in Analog's Valentine's Day event on the platform for a chance to win rewards. Important Information: Lava Network Round Seed Amount $15M Investors Hashkey Capital, Triple Capital Lava Network aims to be a marketplace for blockchain data. It incentivizes node providers and decentralized application users to enter marketplace blockchain data onto its network in the same way that Airbnb allows owners to monetize their unused space. The protocol enforces data quality, enabling node operators to use their bandwidth. Fordefi Round / Amount $10M Investors Electric Capital, Paxos Fordefi is an institutional MPC wallet and security platform that enables institutions to interact across different blockchains. Sphinx Round Pre-Seed Amount $2M Investors Archetype, Nascent Sphinx is a DevOps platform for deploying and managing smart contracts built for Foundry users. Sphinx gives developers confidence in their deployment process by eliminating the manual work of creating, approving, executing, and verifying deployments on every chain. NodeKit Round / Amount / Investors a16z, Polygon Ventures NodeKit SEQ is a decentralized shared sequencer built into a custom L1 blockchain, which allows rollups to decentralize their sequencer and increase cross-rollup interoperability. With NodeKit, SEQ rollups can easily submit transactions to a decentralized shared sequencer, which makes it easier to launch a rollup that is decentralized from the start and helps users perform cross-rollup transactions. WITNESS Round Seed Amount $3.5M Investors Coinbase, Haun Ventures Witness unlocks Web3 ownership and incentives at the Web2 scale. Anyone can use Witness to create verifiable provenance and issue digital ownership for any data without the upfront friction or cost of blockchains. This allows developers to build traditionally scalable applications that benefit from Web3 incentives. DePHY Round Seed Amount / Investors Foresight Ventures DePHY is an all-in-one DePIN framework that drastically decreases the cost and timeframe associated with DePIN project development. DePHY provides open-source hardware solutions, a decentralized messaging layer, and automatic tokenomics execution for all DePIN projects. DePHY’s messaging layer facilitates the secure, verifiable, and swift transfer of data from hardware to the blockchain, utilizing Trusted Execution Environment (TEE) and Zero-Knowledge (ZK) Oracles to guarantee data verifiability and low latency. DeFi Ethena Round Strategic Amount $14M Investors Dragonfly, BH Digital Ethena is building derivative infrastructure to enable Ethereum to transform into the Global Internet Bond via delta-neutral positions on stETH, to create the first crypto-native, yield-bearing stablecoin: USDE. Concrete Round / Amount $7.5M Investors Hashed, Tribe Capital Concrete is the native base protocol to generate credit products and derivatives. It additionally opens the gateway to build an entirely new set of financial primitives for on-chain assets using Concrete as the base layer of compute. At launch, Concrete will serve users across money markets such as Aave, Compound, Silo, and Radiant, regularly adding both established and emerging lenders. IntentX Round Strategic Amount $1.8M Investors Selini Capital, Mirana Ventures IntentX is an intent-based, decentralized derivatives exchange offering perpetual futures trading. The platform leverages several cutting-edge technologies, including LayerZero, a cross-chain communication protocol, account abstraction, and a zero-to-one breakthrough Request for Quotation (RFQ) architecture that addresses critical challenges in delivering on-chain derivatives. Hydro Protocol Round / Amount / Investors Vessel Capital, Injective Hydro Protocol is Injective Uehara Raw Quality Pressing Raw Product Partnership. 1:1 proportionate press INJ in the Injective community. Hydro's unique treatment is based on the underlying liquidity provider, which is a stimulating liquidity provider. GameFi Overworld Round Seed Amount $10M Investors Hashed, Spartan Group Overworld is a web-3-powered gaming and community project. It focuses on collective storytelling, utility-driven digital collectibles, and deep, engaging multiplayer gameplay. All of this is set in an ambitious fantasy universe. Ultiverse Round Strategic Amount $4M Investors Binance Labs, IDG Capital, Animoca Brands Ultiverse is the social gaming metaverse that connects Web3 with an immersive, fully VR-compatible virtual world of AAA quality. By empowering players of various economic abilities to build mutually beneficial relationships, Ultiverse aims to create a first-of-its-kind MetaFi. Exverse Round Private Amount $3M Investors Cogitent Ventures, Moonrock Capital Exverse is a free-to-play game bringing a fresh take on AAA first-person-shooters to Web3. Exverse’s three planets—Social, Quest, and Battle—cater to different playing styles while remaining interconnected within a single timeline, where users compete in cycles known as seasons, lasting eight weeks. The game is designed to foster community by allowing players to engage in social events and even develop user-generated worlds within an ever-expanding universe. NFT Watches.io Round Pre-Seed Amount $1.9M Investors Lemniscap, Big Brain Holdings Watches.io is the first end-to-end tracking and trading ecosystem for watches, enabling users to monitor their watch portfolios with precise, real-time market data, pursue diversification opportunities, and execute seamless buy/sell transactions. Watches.io is also the first e-commerce peer-to-peer marketplace for real physical items to be built on Web3 infrastructure. MetaStreet Round / Amount $25M Investors DragonFly,  Animoca Brands MetaStreet is a protocol for scaling liquidity in NFT credit markets. Its primary product is a Capital Vault that enables secondary market liquidity for NFT-backed notes. Participants can deposit capital to earn yield from diversified portfolios of NFT-backed notes. Tools Helika Round Series A Amount $8M Investors Big Brain Holdings, Fenbushi Helika is a Web3 technology platform that provides real-time analytics and onboarding of new users to gaming studios and popular NFT collections. With a focus on integrating analytics from Web2, in-game, on-chain, and social media data, Helika helps top Web3 brands such as Yuga Labs and Treasure to understand their communities, increase user acquisition and engagement, and drive overall growth through a data-driven approach. Others Drosera Network Round Pre-Seed Amount $1.5M Investors Anagram, Arrington Capital Drosera is a decentralized incident response protocol that leverages hidden security intents to contain and mitigate exploits. It is an automation protocol that abstracts the complexity of creating monitoring systems and automated response capability for decentralized applications. Drosera offers a framework for creating and executing automated responses to events on the Ethereum network. MercureDAO Round / Amount $1.5M Investors / Mercure DAO is a Web3 Marketing Hub catering to crypto projects worldwide, such as Incubation Services, Social Media Marketing (SMM), Influencer Marketing, Public Relations (PR), and so on. Metropolis Round / Amount $1.2M Investors Protocol Labs, Outlier Ventures Metropolis is a carefully curated, artist-created virtual world complete with a digital-physical marketplace, exclusive events, and end-to-end game features. At the heart of MetropolisX is a collaboration marketplace where creators can monetize and launch personalized products and where their fans can have a more immersive connection and access exclusive products, content & experiences. This unique approach combines digital and physical identity, gaming, and immersive experiences. CeFi Architect Round / Amount $12M Investors BlockTower Capital, Tioga Capital Architect provides traders with an adaptable infrastructure that redefines access to global digital asset markets, making it easier for large investors such as institutions to use both centralized and decentralized crypto markets.

The Crypto Investment Weekly Recap for Feb 12 - Feb 18

Sound Call Graph Construction for Java Object: Conclusions, Acknowledgment, & References

Authors: (1) Maggie D. Bailey, Colorado School of Mines and National Renewable Energy Lab; (2) Douglas Nychka, Colorado School of Mines; (3) Manajit Sengupta, National Renewable Energy Lab; (4) Aron Habte, National Renewable Energy Lab; (5) Yu Xie, National Renewable Energy Lab; (6) Soutir Bandyopadhyay, Colorado School of Mines. Table of Links Abstract and Intro Data Bayesian Hierarchical Model (BHM) Solar Radiation Example Results Conclusion Appendix A: Simulation Study Appendix B: Regridding Coefficient Estimates References References Accadia, C., Mariani, S., Casaioli, M., Lavagnini, A., and Speranza, A.: Sensitivity of precipitation forecast skill scores to bilinear interpolation and a simple nearest-neighbor average method on high-resolution verification grids, Weather and forecasting, 18, 918–932, 2003. Berndt, C. and Haberlandt, U.: Spatial interpolation of climate variables in Northern Germany—Influence of temporal resolution and network density, Journal of Hydrology: Regional Studies, 15, 184–202, 2018. Chandler, R., Barnes, C., Brierley, C., and Alegre, R.: Regridding and interpolation of climate data for impacts modelling–some cautionary notes, Tech. rep., Copernicus Meetings, 2022. Cressie, N. and Wikle, C. K.: Statistics for Spatio-Temporal Data, 2011. Cressie, N. A.: Change of support and the modifiable areal unit problem, 1996. Diaconescu, E. P., Gachon, P., and Laprise, R.: On the remapping procedure of daily precipitation statistics and indices used in regional climate model evaluation, Journal of Hydrometeorology, 16, 2301–2310, 2015. Ensor, L. A. and Robeson, S. M.: Statistical characteristics of daily precipitation: comparisons of gridded and point datasets, Journal of Applied Meteorology and Climatology, 47, 2468–2476, 2008. Finley, A. O., Banerjee, S., and Gelfand, A. E.: spBayes for large univariate and multivariate point-referenced spatio-temporal data models, arXiv preprint arXiv:1310.8192, 2013. Gelfand, A. E., Zhu, L., and Carlin, B. P.: On the change of support problem for spatio-temporal data, Biostatistics, 2, 31–45, 2001. Handcock, M. S. and Stein, M. L.: A Bayesian analysis of kriging, Technometrics, 35, 403–410, 1993. Harris, T., Li, B., and Sriver, R.: Multi-model Ensemble Analysis with Neural Network Gaussian Processes, arXiv [preprint] arXiv:2202.04152, 2022. Loghmari, I., Timoumi, Y., and Messadi, A.: Performance comparison of two global solar radiation models for spatial interpolation purposes, Renewable and Sustainable Energy Reviews, 82, 837–844, 2018. McGinnis, S. and Mearns, L.: Building a climate service for North America based on the NA-CORDEX data archive, Climate Services, 22, 100 233, 2021. McGinnis, S., Mearns, L., and McDaniel, L.: Effects of Spatial Interpolation Algorithm Choice on Regional Climate Model Data Analysis, "Fall Meeting, American Geophysical Union, San Francisco", 2010. Phillips, D. L. and Marks, D. G.: Spatial uncertainty analysis: propagation of interpolation errors in spatially distributed models, Ecological Modelling, 91, 213–229, 1996. Rajulapati, C. R., Papalexiou, S. M., Clark, M. P., and Pomeroy, J. W.: The perils of regridding: examples using a global precipitation dataset, Journal of Applied Meteorology and Climatology, 60, 1561–1573, 2021. Rauscher, S. A., Coppola, E., Piani, C., and Giorgi, F.: Resolution effects on regional climate model simulations of seasonal precipitation over Europe, Climate dynamics, 35, 685–711, 2010. Sengupta, M., Xie, Y., Lopez, A., Habte, A., Maclaurin, G., and Shelby, J.: The national solar radiation data base (NSRDB), Renewable and sustainable energy reviews, 89, 51–60, 2018. Whittemore, A. S.: Errors-in-variables regression using Stein estimates, The American Statistician, 43, 226–228, 1989. This paper is under CC 4.0 license. available on arxiv

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