Our mission is to champion homeowners on their financial journey, as the partner they trust with their home and future

Valon

Scientific American, Volume XXIV., No. 12, March 18, 1871 by Various, is part of the HackerNoon Books Series. You can jump to any chapter in this book . Official lists of patents here Official lists of patents ISSUED BY THE U. S. PATENT OFFICE. FOR THE WEEK ENDING MARCH 7, 1871. Reported Officially for the Scientific American. SCHEDULE OF PATENT FEES On each Caveat $10 On each Trade-Mark $25 On filing each application for a Patent, (seventeen years) $15 On issuing each original Patent $20 On appeal to Examiners-in-Chief $10 On appeal to Commissioner of Patents $20 On application for Reissue $30 On application for Extension of Patent $50 On granting the Extension $50 On filing a Disclaimer $10 On an application for Design (three and a half years) $10 On an application for Design (seven years) $15 On an application for Design (fourteen years) $30 For Copy of Claim of any Patent issued within 30 years $1 A sketch from the model or drawing, relating to such portion of a machine as the Claim covers, from upward, but usually at the price above-named. $1 The full Specification of any patent issued since Nov. 20, 1866 at which time the Patent Office commenced printing them $1.25 Official Copies of Drawings of any patent issued since 1836, we can supply at a reasonable cost, the price depending upon the amount of labor involved and the number of views. Full information, as to price of drawings, in each case, may be had by addressing MUNN & CO., Patent Solicitors, 37 Park Row, New York. 112,309.—Hose Sprinkler.—William Anderson, San Francisco, Cal. 112,310.—Locomotive Spark Arrester.—J. G. Armstrong, New Brunswick, N. J. 112,311.—Tool for Carriage Makers' Use.—George Atkinson, San Francisco, Cal. 112,312.—Potato Probe.—John A. Beal, Waterford, N. Y. 112,313.—Hinge for Carriage Doors.—George W. Beers, Bridgeport, Conn. 112,314.—Stove Leg.—James Birckhead, Jr., Baltimore, Md. 112,315.—Clothes Pin.—Orris A. Bishop, Chicago, Ill. 112,316.—Manufacture of Rochelle Salts and Borax.—V. G. Bloede, Brooklyn, N. Y. 112,317.—Beehive.—Felix Brewer, Waynesville, Mo. 112,318.—Thill Coupling.—Theodore Burr (assignor to Allen Muir and Henry Muir), Battle Creek, Mich. 112,319.—Evaporating Pan for Saccharine Liquids.—F. C. Butler, Bellows Falls, Vt., assignor to himself and James B. Williams, Glastonbury, Conn. 112,320.—Door Securer.—William H. Caldwell, Wheeling, W. Va. 112,321.—Toe-calk Bar.—R. B. Caswell, Springfield, Mass. Antedated March 2, 1871. 112,322.—Glass Flattening Furnace and Leer.—James Clabby, Lenox, Mass. 112,323.—Spring Bed Bottom.—Alex. Cole, Manamuskin, N. J. 112,324.—Water Wheel.—E. E. Coleman, West Cummington, Mass. 112,325.—Toy Horse and Carriage.—John B. Cuzner, Bridgeport, Conn. 112,326.—Mackerel-line Holder.—E. L. Decker, Southport, Me. 112,327.—Sewing Machine.—J. William Dufour, Stratford, Conn. 112,328.—Steam Boiler.—Edwards Evans, North Tonawanda, N. Y. 112,329.—Medical Compound for Cure of Catarrh and Asthma.—Erastus Field, Ostrander, Ohio. 112,330.—Machine for Grinding the Cutters of Mowers, etc.—H. C. Fisk, Wellsville, N. Y. 112,331.—Machine for Making Hooks and Eyes.—Jeremy T. Ford, San Francisco, Cal. 112,332.—Churn.—Thompson Freeman, Westfield, Ill. 112,333.—Attachment for Revolving Mold Boards for Plows.—J. S. Godfrey, Leslie, Mich., assignor to himself and S. M. Loveridge, Pittsburgh, Pa. 112,334.—Grain Cleaner and Fertilizer Sifter.—J. A. Green, Mill Dale, Va. 112,335.—Screw Propulsion.—E. C. Gregg (assignor to A. H. Gregg and C. P. Gregg), Trumansburg, N. Y. 112,336.—Seeding Machine.—P. M. Gundlach, Belleville, Ill. 112,337.—Compound for Kindling Fires.—J. L. Hannum and S. H. Stebbins, Berea, Ohio. 112,338.—Lawn Mower.—Benjamin Harnish, Lancaster, and D. H. Harnish, Pequea, Pa. 112,339.—Composition for Pavements.—C. B. Harris, New York city. Antedated February 25, 1870. 112,340.—Spring for Vehicles.—John R. Hiller, Woodland, Cal. 112,341.—Harvester Rake.—S. T. Holly, (assignor to John P. Manny), Rockford, Ill. 112,342.—Door Clamp.—Henry O. Hooper, Diamond Springs, Cal. 112,343.—Taper Holder.—Thomas W. Houchin, Morrisania, N. Y. 112,344.—Metallic Garter.—Henry A. House, Bridgeport, Conn. 112,345.—Bobbin Winder.—Henry A. House, Bridgeport, Conn. 112,346.—Method of Knitting Stockings, etc.—Henry A. House, Bridgeport, Conn. 112,347.—Apparatus for Evaporating and concentrating Liquids.—John Howarth, Salem, Mass. Antedated March 1, 1871. 112,348.—Apparatus for Evaporating and Concentrating Liquids.—John Howarth, Salem, Mass. Antedated March 1, 1871. 112,349.—Apparatus for Removing Oil from Vegetable and other Matters.—Elias S. Hutchinson, Baltimore, Md. 112,350.—Apparatus and Process for Removing Oil from Grain, Seeds, etc.—Elias S. Hutchinson, Baltimore, Md. 112,351.—Chandelier.—Charles F. Jacobsen, New York city. 112,352.—Culinary Vessel.—Carrie Jessup, New Haven, Conn. 112,353.—Machine for Cutting Leather.—Aberdeen Keith, North Bridgewater, Mass. 112,354.—Attaching Knobs to their Spindles.—John F. Keller and Nathaniel Sehner, Hagerstown, Md. 112,355.—Miter Machine.—T. E. King, Boston, Mass. 112,356.—Take-up for Corset Looms.—Julius Kuttner, New York city. 112,357.—Elevator and Carrier.—T. W. Lackore, Worth, Ill. 112,358.—Apparatus for Burning Hydrocarbon Oils.—James R. Lee, Grass Valley, Cal. 112,359.—Burglar Alarm.—Robert Lee, Cincinnati, Ohio. 112,360.—Telegraph Apparatus.—L. T. Lindsey, Jackson, Tenn. 112,361.—Harvester.—J. P. Manny, Rockford, Ill. 112,362.—Harvester.—J. P. Manny, Rockford, Ill. 112,363.—Harvester Rake.—J. P. Manny, Rockford, Ill. 112,364.—Cheese Curd Sink.—H. C. Markham, Collinsville, N. Y. 112,365.—Mowing Machine.—H. C. Markham and Dewitt C. Markham, Collinsville, N. Y. 112,366.—Propeller.—Alex. J. Marshall, Warrenton, Va. Antedated March 3, 1871. 112,367.—Oiler.—Edward McDuff and E. D. Forrow, Warwick, R. I. 112,368.—Wash Boiler.—John McInnes, Oxford, Pa. 112,369.—Propelling Canal Boats.—H. B. Meech, Fort Edward, N. Y. Antedated February 25, 1871. 112,370.—Water-proof Compound for Coating Cloth Wood, Metals, etc.—Peter E. Minor, Schenectady, N. Y. 112,371.—Cooking Stove.—W. N. Moore, Neenah, Wis. 112,372.—Boring Machine.—J. H. Pardieck (assignor to himself and S. M. Brown), Acton, Ind. 112,373.—Vapor Burner.—R. W. Park, Philadelphia, Pa. 112,374.—Machine for Pointing Blanks for Cultivator Teeth.—John Pedder and George Abel, West Pittsburgh, Pa. 112,375.—Bale Tie.—J. E. Perkins, San Francisco, Cal. 112,376.—Lining Walls with Felt, etc.—James Phillips, Chicago, Ill. 112,377.—Cooking Stove.—Samuel Pierce, Boston, Mass. 112,378.—Tack.—A. A. Porter, New Haven, Conn. Antedated Feb. 25, 1871. 112,379.—Machine for Shaping and Cutting Gear Cutters.—F. A. Pratt (assignor to the Pratt & Whitney Company), Hartford, Conn. 112,380.—Combination Camera and Developing Box.—E. C. Ratzell, Philadelphia, Pa. 112,381.—Punching Machine.—J. C. Rhodes, South Abington, Mass. 112,382.—Washing Machine.—J. W. Ricker, Chelsea, Mass. 112,383.—Curtain Fixture.—Charles Robin. Chester, Conn. 112,384.—Machine for Making Printers' Leads.—Isaac Schoenberg, New York city. 112,385.—Slide Valve for Steam Riveting Machines.—Coleman Sellers (assignor to William Sellers & Co.), Philadelphia, Pa. 112,386.—Machine for Polishing Thread.—Samuel Semple, Sr., John Semple, Samuel Semple, Jr., and R. A. Semple, Mount Holly, N. J. 112,387.—Paint Brush.—F. S. Shearer, Washington, Ill. 112,388.—Bee Hive.—S. A. Short, F. J. Short, J. B. Short, and Jasper Kile, Decatur, Ala. 112,389.—Apparatus for Removing Oil from Vegetable and other Matter.—Thomas Sim, Baltimore, Md. 112,390.—Retort for Producing Bisulphide of Carbon.—Thomas Sim, Baltimore, Md. 112,391.—Utilizing the Silky Down of the Wild Cotton. —M. H. Simpson, Boston, Mass. 112,392.—Pruning Shears.—Frank Smiley, Batavia, N. Y. 112,393.—Water-closet Valve.—A. J. Smith, San Francisco, Cal. 112,394.—Gang Plow.—J. W. Sursa, San Leandro, Cal. 112,395.—Grinding Pan and Amalgamator.—W. H. Thoss, West Point, Cal. 112,396.—Street Lantern.—Augustus Tufts, Malden, Mass. 112,397.—Cooking Stove.—Alvin Warren, Swanton, Ohio. 112,398.—Safety Bridle.—James Weatherhead, San José, Cal. 112,399.—Fire Grate.—George Wellhouse, Akron, Ohio. 112,400.—Hay Knife.—G. F. Weymouth, Dresden, Me. 112,401.—Claw Bar.—Charles Winter, Chillicothe, Ohio. 112,402.—Steam Generator.—J. C. Woodhead, Pittsburgh, Pa. 112,403.—Animal Trap.—W. D. Wrightson, Queenstown England. 112,404.—Brush.—John Ames, Lansingburg, N. Y. 112,405.—Clod Fender.—F. L. Bailey, Freeport, Ind. 112,406.—Ruler.—H. S. Ball, Spartanburg, S. C. 112,407.—Fanning Mill.—Benjamin Barney, Time, Ill. 112,408.—Ice-cutting Machine.—Lafayett Barnum (assignor to himself and A. R. Hale), Bridgeport, Conn. 112,409.—Manufacture of Ice.—T. J. Bigger, Kansas City, Mo. 112,410.—Machine for Heading Bolts and Spikes.—Reinhold Boeklen, Brooklyn, N. Y., assignor to himself and Henry Torstrick New York city. Antedated Feb. 28, 1871. 112,411.—Washing Machine.—Joseph Boswell, L. M. Boswell, Jonathan Palmer, and J. H. James (assignors to themselves and Thomas Starbuck), Wilmington, Ohio. 112,412.—Water Wheel.—E. C. Boyles, New York city. 112,413.—Cotton Press.—R. M. Brooks, Pike county, Ga. 112,414.—Paper-cutting Machine.—Samuel Brown (assignor to himself and C. R. Carver), Philadelphia, Pa. 112,415.—Governor for Direct-acting Engines.—A. S. Cameron, New York city. 112,416.—Governor for Direct-acting Engines.—A. S. Cameron, New York city. 112,417.—Butt Hinge.—J. W. Carleton (assignor to the Union Manufacturing Co.), New Britain, Conn. 112,418.—Machine for Cutting Sheet Metal.—C. R. Choate, East Saginaw, Mich. 112,419.—Bit Brace.—William Cleveland, Lawrence, Mass., assignor to himself and James Swan, Seymour, Conn. 112,420.—Steam Engine Governor.—C. A. Condé, Indianapolis, Ind. 112,421.—Carpet-cleaning Machine.—J. C. Craft (assignor to himself and Antonio Rosello), Baltimore, Md. 112,422.—Steam Regulator for Paper Dryers.—Daniel Crosby, Hampden, Me. 112 423.—Metallic Piston and Valve Rod Packing.—G. M. Cruickshank, Providence, R. I. 112,424.—Grain-thrashing and Separating Machine.—John Culham, Grand Rapids, Mich. Antedated Feb. 25, 1871. 112,425.—Cooking Stove.—David Curtis, Mishawaka, assignor to himself and C. B. Graham, South Bend, Ind. 112,426.—Lightning Rod.—S. D. Cushman, New Lisbon, Ohio. 112,427.—Hose Bridge.—Patrick Daily (assignor to himself and J. J. Kehoe), New York city. 112,428.—Cover for Openings in Sidewalks.—William Dale, New York city. 112,429.—Rotary Pump.—F. O. Deschamps, Philadelphia, Pa. 112,430.—Machine for Cutting Files.—James Dodge, Manchester, England, assignor to David Blake, Spencertown, N. Y. 112,431.—Coupling for Railway Cars.—Henry Dubs and S. G. Goodall-Copestake, Glasgow, Great Britain. 112,432.—Tobacco Pipe.—P. J. Dwyer, Elizabethport, N. J. 112,433.—Basket for House Plants.—Albert P. Eastman, Washington, D. C. 112,434.—Sulky Plow.—Milo A. Elliott, Stratford Hollow, N. H. 112,435.—Stretcher for Paintings.—James Fairman, New York city. 112,436.—Body Lantern Holder.—Samuel C. Fessenden, Stamford, Conn. 112,437.—Stove Leg.—Amon L. Finch, Sing Sing, N. Y. 112,438.—Pump Piston.—John S. Follansbee and George Doolittle (assignors to the Forrester Manufacturing Company), Bridgeport, Conn. 112,439.—Shoe.—Samuel W. Francis (assignor to himself and W. H. Newton), Newport, R. I. 112,440.—Guard-Finger for Harvesters.—George Fyfe and Chester Hard, Ottawa, Ill. 112,441.—Dining Table.—S. R. Gardner (assignor to himself and S. M. Marquette), Independence, Iowa. 112,442.—Step Ladder.—M. Boland Geary, New York City. 112,443.—Oilcloth Printing Machinery.—Ebenezer A. Goodes (assignor to Philadelphia Patent and Novelty Company), Philadelphia, Pa. 112,444.—Tenoning Machine.—Lyman Gould, Norwich, Conn. 112,445.—Printer's Case.—Wm. H. A. Gresham, Atlanta, Ga. 112,446.—Lamp Chimney.—Geo. W. Griswold, Factoryville, Pa. 112,447.—Grain Separator.—Philander Griswold, Hudson, Mich. 112,448.—Clamp for Thill Couplings.—John W. Guider (assignor to himself and John Kiefer), St. Joseph, Mo. 112,449.—Bird Cage.—Gottlob Gunther, New York city. 112,450.—Stop Cock and Valve.—William Haas, New York city. 112,451.—Valve for Steam Engines.—Joseph L. Harley, Baltimore, Md., and Xaver Fendrich, Georgetown, D. C. 112,452.—Metallic Hub.—John H. Harper, Pittsburgh, Pa. 112,453.—Composition for Lubricating Machinery.—E. Q. Henderson (assignor to John C. Burroughs and Richard A. Springs) Charlotte, N. C. 112,454.—Post-hole Digger.—Bryant B. Herrick, Decatur, Mich. 112,455.—Door Check.—Levi S. Hicks (assignor to himself, J. Perrin Johnson, and John Buell), Peoria, Ill. 112,456.—Railway-car Brake.—Luther Hill, Stoneham, and Seth D. Tripp, Lynn, Mass. 112,457.—Truss.—Adam Hinoult, Montgomery, N. Y. 112,458.—Feed Bag for Horses.—Walter A. Hough, South Butler, N. Y. 112,459.—Shade Holder for Lamps—Mark W. House, Cleveland, Ohio. 112,460.—Lamp Chimney.—Mark Wiggins House (assignor to the Cleveland Non-Explosive Lamp Company), Cleveland, Ohio. Antedated March 1, 1871. 112,461.—Horse Hay Rake.—James Howard and E. T. Bousfield, Bedford, England. 112,462.—Tongs for Rolling Barrels.—Mark W. Ingle, Indianapolis, Ind. 112,463.—Pitman.—George W. Jayson, Lodi, Ohio. 112,464.—Paste for Paper Hangings.—John Jones (assignor to himself and Henry A. Smith), New York city. 112,465.—Twine Holder.—Edward M. Judd, New Haven, Ct. 112,466.—Clothes Pin or Clasp.—Amos L. Keeports and William Yount, Littletown, Pa. 112,467.—Putting up Hams.—Samuel Edward Kelly, Philadelphia, Pa. 112,468.—Limn Kiln.—Thomas A. Kirk, Kansas City, Mo. 112,469.—Fastening for Seats for Wagons or Sleighs.—John G. Knapp and John F. Robertson (assignors of one third their right to James H. Holly), Warwick, N. Y. 112,470.—Potato Planter.—George Knowlton (assignor for one-half his right to N. Haynes), Johnstown, Pa. 112,471.—Revolving Firearm.—Edwin S. Leaycroft, Brooklyn, N. Y., assignor by mesne assignment, to "Colt's Patent Firearms Manufacturing Company," Hartford, Conn. 112,472.—Revolving Firearm.—Edwin S. Leaycroft, Brooklyn, N. Y., assignor, by mesne assignment, to "Colt's Patent Firearms Manufacturing Company," Hartford, Conn. 112,473.—Railroad Cattle-Guard Gate.—J. H. Mallory, La Porte, Ind. 112,474.—Back-reflecting Mirror.—Richard Mason (assignor to himself and Matthew Ely), Newark, N. J. 112,475.—Ventilator and Chimney Top.—James McGowan (assignor to himself and Daniel H. Waring), New York city. 112,476.—Apparatus for Rectifying and Refining Spirits.—Frederick Measey (assignor to himself and Henry D. Fling), Philadelphia, Pa. 112,477.—Tin Can.—John F. Merrill (assignor to himself and Alexander Stewart), Cincinnati, Ohio. 112,478.—Take-up Mechanism for Looms.—John Michna and Joseph Fischer, New York city. 112,479.—Combined Baker and Broiler.—Wm. H. Miller, Brandenburg, Ky. 112,480.—Shuttle for Sewing Machines.—James D. Moore, Grinnell, Iowa. 112,481.—Cotton Chopper and Grain Cultivator.—Daniel Mosely, Osark, Arkansas. 112,482.—Sad and Fluting Iron.—Frederick Myers, New York city. 112,483.—Reed for Organs and Melodeons.—Augustus Newell, Chicago, Ill. 112,484.—Straw Cutter.—Amon Park, Germanville, Iowa. 112,485.—Apparatus for Aging Whisky and Other Spirits.—Josiah Peiffer and Samuel Richards, Valonia, Pa. 112,486.—Combined Cotton and Corn Planter.—Louis A. Perrault (assignor to himself and Joseph Huber), Natchez, Miss. 112,487.—Faucet.—Solomon Pfleger, Reading, assignor to himself and J. S. Pfleger, Tamaqua, Pa. 112,488.—Treadle.—George K. Proctor, Salem, Mass. 112,489.—Lubricating Compound.—Victory Purdy, Poughkeepsie, N. Y. 112,490.—Fertilizer and Seeding Machine.—Archibald Putnam (assignor to Elizabeth Putnam), Owego, N. Y. 112,491.—Rotary Pump.—George W. Putnam, South Glens Falls, N. Y. 112,492.—Hat Brush.—Robert Dunbar Radcliffe, Palmyra, N. Y. 112,493.—Refrigerating Show Case.—Thomas L. Rankin, Lyndon, Kansas, assignor to himself and D. W. Rockwell, Elyria, Ohio. 112,494.—Device for Starting and Stopping Cars.—Philip Rhoads, Carlisle, Pa. 112,495.—Pipe-molding Machine.—George Richardson, Milwaukee, Wis. 112,496.—Sulky Cultivator.—Richard B. Robbins, Adrian, Mich. 112,497.—Hand Plow.—Nelson Rue, Harrodsburg, Ky. 112,498.—Mechanical Movement.—Edward G. Russell, Ravenna, Ohio. 112,499.—Railway Car Brake.—Lyman Alphonzo Russell, Shrewsbury, Vt. 112,500.—Stovepipe Cleaner.—David Sanford, Ashton, Ill. 112,501.—Twine Holder.—Joseph B. Sargent and Purmont Bradford (assignors to Sargent & Co.), New Haven, Conn. 112,502.—Dovetailing Machine.—James M. Seymour, Newark, N. J. 112,503.—Wooden Pavement.—Eaton Shaw, Portland, Me. 112,504.—Guard for Circular Saws.—George W. Shipman, Ischua, N. Y. 112,505.—Breech-loading Firearm.—Dexter Smith and Martin J. Chamberlin, Springfield, Mass. 112,506.—Spark Arrester.—James Smith, Altoona, Pa. 112,507.—Horse Hay Rake.—Solomon P. Smith, Waterford, N. Y. 112,508.—Plow.—S. M. Stewart, New Harrisburg, Ohio. 112,509.—Medical Compound for Treating Fever and Ague.—George E. Swan, Mount Vernon, Ohio. 112,510.—Device for Cooling Journals of Car Axles.—Henry G. Thompson, Milford, Conn. 112,511.—Cooling Journal of Car Axles.—Henry G. Thompson, Milford, Conn. 112,512.—Cooling Journal of Car-wheel Axles.—Henry G. Thompson, Milford, Conn. 112,513.—Device for Cooling Journals of Railway Cars.—Henry G. Thompson, Milford, Conn. 112,514.—Non-heating Handle for Sad Irons, etc.—William H. Towers, Boston, Mass. 112,515.—Lubricator.—John Erst Uhl, Renovo, Pa. 112,516.—Combined Corn Planter and Cultivator.—Franklin Underwood, South Rutland, N. Y. 112,517.—King Bolt.—Wendel Vondersaar, Indianapolis, Ind. 112,518.—Wheat Roaster.—George W. Waitt (assignor to himself and Robert B. Fitts), Philadelphia, Pa. 112,519.—Plaster Sower.—Thomas J. West, Alfred Center, N. Y. 112,520.—Ticket Holder.—Henry Wexel, Providence, R. I. 112,521.—Tobacco Press.—Abraham N. Zell, Lancaster, Pa. 112,522.—Combined Bag Holder and Scales.—William Zimmerman, Lebanon, Pa. Antedated February 25, 1871. 112,523.—Breech-loading Firearm.—James M. Mason, Washington, D. C. 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. Various (2006). Scientific American, Volume XXIV., No. 12, March 18, 1871. Urbana, Illinois: Project Gutenberg. Retrieved https://www.gutenberg.org/cache/epub/19180/pg19180-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

Official lists of patents

Scientific American Supplement, No. 711, August 17, 1889, by Various, is part of the HackerNoon Books Series. You can jump to any chapter in this book . NOTES ON DYEWOOD EXTRACTS AND SIMILAR PREPARATIONS. here NOTES ON DYEWOOD EXTRACTS AND SIMILAR PREPARATIONS. By Louis Siebold, F.I.C., F.C.S. During the last ten years there has been an enormous increase in the production of these preparations, and the time will come when their application in dyeing and calico printing will become so general as to completely supersede the employment of the raw materials. The manufacture of these extracts, to be thoroughly successful, requires to be so conducted as to secure the perfect exhaustion of the dyewoods without the slightest destruction or deterioration of the coloring matters contained in them; and though nothing like perfection has been reached in the attainment of these objects, it is certain that the processes of extraction and evaporation now employed by the best makers are a very great improvement on the older methods. Indeed, there is no difficulty nowadays in procuring dyewood extracts of high excellence if the consumer is willing to pay a price for them corresponding to their quality, and knows how to avail himself of the aid of chemical skill to control his purchases. Unfortunately, however, there is so much hankering after cheap articles, and so little care is taken to ascertain their real quality, that every scope is afforded to the malpractices of the adulterer. There are many dye and print works in which large quantities of these extracts are used without being subjected to trustworthy tests. Moreover, much of the testing is done by fallacious methods and often by biased hands. So fallacious, indeed, are some of these tests, that grossly adulterated extracts are often declared superior to the purer ones, the cause of this being the application of an insufficient proportion of mordant in the dyeing or printing trials, and the consequent waste of the excess of coloring matter in the case of the purer preparation. Professional analytical chemists have hitherto given but little attention to these preparations, and the employment of experienced chemists in works is as yet far from general. The testing of dyewood extracts in such a manner as to throw full light on their purity, the quality of raw material from which they are prepared, their exact commercial value their suitability for special purposes, and the proportion and nature of any adulterants they may contain, is of course a difficult and tedious task, and must be left to the expert who is in possession of authentic specimens prepared by himself of all the different extracts made from every variety and quality of raw materials, and who combines a thorough knowledge of experimental dyeing and printing with a large experience in the chemical investigation of these preparations. But when the object of the testing is merely careful comparison of the sample in question with an original sample or previous deliveries, the case is much simplified, and comes within the scope of the general chemist or the laboratory attached to works. A few years ago I recommended carefully conducted dyeing trials on woolen cloth mordanted with bichromate of potash as the best and simplest mode adapted to such cases, and my subsequent experience enables me to confirm that observation to the fullest extent. Most of these extracts contain the coloring matter in two states, the developed and the undeveloped, and an oxidizing mordant such as bichromate of potash causes the latter as well as the former to enter completely into combination with a metallic base; whereas many of the other mordants, such as alumina or tin compounds, merely take up the developed portion of the coloring matter together with such small and variable proportions of the undeveloped as might undergo oxidation during the process of dyeing. I would therefore suggest dyeing trials with alumina, tin, iron, etc., only as subsidiary tests indicating the suitability of an extract for certain special purposes, while recommending the trial with bichromate of potash as the one giving the best information respecting the actual strength of the extract in relation to the raw material from which it was obtained, and as giving a fair idea of the money value of the sample. Cotton dyeing does not, as a general rule, afford a good means of assaying extracts, as it is generally done under conditions which do not admit of complete exhaustion of the dye bath, but it might often with advantage be resorted to as an additional trial throwing further light on the degree of oxidation or development of the coloring matter. Printing trials are apt to give fallacious results unless the proportion of mordant is carefully adjusted to the amount of coloring matter present, and several trials with different proportions would be necessary to prevent erroneous conclusions. For the trials with bichromate of potash on wool I would recommend pieces of cloth weighing about 150 grains, and the most suitable proportion of bichromate of potash is 3 per cent. of the weight of the cloth. The requisite number of pieces (equal to the number of samples to be tested) should be thoroughly scoured and then heated in the bichromate solution at or near the boiling point for not less than 1½ hours, after which they should be well washed and then dyed separately in the solutions of equal weights of the extracts at the same temperature and for the same length of time; 15 grains of extract is a suitable quantity for a first trial under these conditions. These trials can then be repeated with different relative proportions of extract in order to ascertain what weight of a sample would give the same depth of color as 15 grains of the standard example. Many precautions are required both in the mordanting and dyeing processes in order to obtain trustworthy results; and though the trials with bichromate of potash give the most reliable information of any single test, they should be supplemented by the subsidiary tests already alluded to, and also by a chemical examination, in order to obtain a knowledge, not merely of the wood strength, but also of the general nature of the extract. An adulteration with molasses or glucose can be best determined by fermentation in comparison with a pure sample. Mineral adulterants may, of course, be detected by an estimation and analysis of the ash, after making due allowances for variations due to differences in different kinds of the same dyewoods. The estimation of the individual coloring matters in these extracts by means of a chemical analysis is under all circumstances a task requiring much experience, especially as the coloring principles are associated in different qualities of each class of dyewood with different proportions of other constituents which often give much trouble to the unpracticed experimenter. Extracts made from logwood roots are now largely manufactured and often substituted or mixed with the extracts of real logwood, and have in some instances been palmed of as logwood extracts of high quality. The correct determination of such admixtures, like the fixing of anything like the exact commercial value of dyewood extracts, requires nothing less than a complete chemical investigation coupled with numerous dyeing trials in comparison with standard preparations, and should be left to an expert. The presence in dyewood extracts of coloring matters in various stages of development has hitherto militated against their use in place of the raw materials by many dyers and printers who are still employing inherited and antiquated processes in which the whole of the coloring matter is not rendered available. It is often asserted by these that even the best of extracts fail to give anything like the results attained by the use of well-prepared woods, and that, indeed, their application proves a complete failure. Such failure, however, is simply due to the want of chemical knowledge on the part of the dyers, for there is no real difficulty in making any good and pure extract serve all the purposes for which the woods were used. It is to be hoped that in this branch of industry, as well as in many others, the employment of chemists will become more general than at present, and not be restricted, as is often the case, to young men without experience and without the trained intellect so essential to success in chemical investigations. High class chemical skill is of course available to the manufacturer, but the man of science who brings matured knowledge and valuable brain work into the business required social as well as pecuniary recognition, and the sooner and more fuller this fact is appreciated the better it will be for the maintenance and progress of our industries. With regard to the astringent extracts, such as sumac, myrabolam, divi, valonia, quebracho, oak, etc., it is the aim of the manufacturer, whenever such extracts are intended for the purposes of dyeing and printing, to obtain the tannin in a form in which it is best calculated to fix itself upon the fiber. The case is somewhat different when the same extracts are required for tanning. For this purpose it is necessary that the extract shall have considerable permeating power, and that the tannin contained in it shall readily yield leather of the desired texture, color, and permanency. Extracts specially suited for this purpose are by no means always the most suitable for the dyer, and . vice versa A brief description of the processes by which the astringent extracts may be tested with particular reference to their fitness for definite purposes concluded the paper. With regard to the question as to whether experimental dyeing with bichromate of potash should be employed as a test even in works where all the dyeing was done with other mordants, he was decidedly of opinion that it should always be resorted to as one of the tests, inasmuch as it was the only simple and expeditious method giving a fair idea of the actual wood strength and money value of the extract. The test should, in such cases, be supplemented by dyeing trials with the mordants used at the works, and, if necessary, also by a chemical analysis. Printing trials were not necessarily bad tests, since oxidizing was usually added in these where it was necessary, and any undeveloped coloring matter would thus be oxidized during the steaming process: but, as he had stated before, it was essentially necessary in such cases to have a fair idea of the amount of actual coloring matter in the extract and to adjust the proportion of mordant accordingly. Such trials should therefore be preceded by carefully conducted dyeing trials with bichromate of potash. Mr. Thomson had raised the question whether it would not be well for the manufacturer to prepare these extracts in such a manner that they would contain all the coloring matter in one condition only, in order to insure greater uniformity in their quality and mode of application. This would, no doubt, be a desirable step to take if the owners of dye and print works were more in the habit of availing themselves of the service of competent chemists experienced in this branch, for then they would be able to make any extract do its full work irrespective of the state of development of the coloring matter. Such, however, was not the case, and it was a very common thing for the consumer of dyewood extracts to require the manufacturer to prepare them specially for him so as to suit his own dyeing recipes, or in other words to give exactly the same shades, weight for weight, by his own method of dyeing as the article he was in the habit of using. The manufacturer was thus often compelled to make many different qualities of the same extract to suit different customers. For the same reason adulterated articles were often preferred to the pure ones. There was, perhaps, no branch of industry in which chemical skill of a high order could be applied with greater advantage than in dyeing, and nowhere was this fact less recognized. Some of the processes of dyeing were exceedingly wasteful and stood in much need of improvement. He (Mr. Siebold) knew a large works in which a ton of logwood extract was used daily for black dyeing only, and he might safely assert that of this enormous quantity only a very small proportion would be fixed on the fiber, while by far the greater proportion was utterly wasted. Such a waste could only be prevented by a searching investigation of its causes by trained skill. Mr. Thomson had further alluded to the color obtained with logwood or logwood extract and wool mordanted with bichromate of potash, and seemed to be under the impression that the color thus obtained was not black, but blue. This was undoubtedly the case in dyeing trials performed as tests, as these were conducted purposely with a very small proportion of coloring matter in order to admit of a better comparison of the resulting depth of shades. But with larger proportions of logwood the color obtained was a fine bluish-black, and with the addition of a small proportion of fustic or quercitron bark to the logwood a jet black was readily produced. With regard to Mr. Watson Smith's observation as to fractional dyeing, he (Mr. Siebold) did not regard this method as a suitable trial for ascertaining the strength of an extract, but he admitted it was occasionally very valuable for detecting an admixture of extracts of other dyewoods, such as quercitron bark extract in logwood extract. It was also a good method of ascertaining the speed of dyeing and hence the relative proportion of fully developed coloring matter of an extract.— Jour. Soc. Chem. Industry. 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. Various (2004). Scientific American Supplement, No. 711, August 17, 1889. Urbana, Illinois: Project Gutenberg. Retrieved https://www.gutenberg.org/cache/epub/16972/pg16972-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

NOTES ON DYEWOOD EXTRACTS AND SIMILAR PREPARATIONS

Hello everyone, in the , I started describing my experience of developing a Python Telegram bot for checking the operability and monitoring of my service located on a remote server. In a nutshell, when you're working on a pet project or even some work tasks, you might want to have all the current system status information at hand (I particularly like the ability to see everything and manage it through a Telegram bot) without spending a lot of time on development. previous article In the previous part, we looked at a way to get instant metrics on demand. In this part, we will be doing simple alerting, i.e., receiving a message in the bot when the system starts to fail. In the next third part, we will cover the case of collecting analytics and receiving online charts. As in the previous part, the example will be based on a real task, but I will be marking those places in the code that you can change to your logic so that the main part of the example can be reused. In this case, I need to get an alert in the form of a message in the Telegram bot in the event that the node I'm interested in loses network connection (or for some other reason), but its last synchronized block is lagging behind the network's last block. As before, we first need to set up the virtual environment: cd ~
virtualenv -p python3.8 up_env # creating an environment
source ~/up_env/bin/activate # activating the environment and install the necessary dependencies: pip install python-telegram-bot
pip install "python-telegram-bot[job-queue]" --pre
pip install --upgrade python-telegram-bot==13.6.0 # the code was written in the times before version 20, so here the version is explicitly specified

pip install numpy # needed for the median value function
pip install web3 # needed for requests to nodes (replace with what you need) The file does not undergo changes in this case and remains the same as in the previous part: functions.py import numpy as np
import multiprocessing

from web3 import Web3 #  add those libraries needed for your task

# Helper function that checks a single node
def get_last_block_once(rpc):
    try:
        w3 = Web3(Web3.HTTPProvider(rpc))
        block_number = w3.eth.block_number
        if isinstance(block_number, int):
            return block_number
        else:
            return None
    except Exception as e:
        print(f'{rpc} - {repr(e)}')
        return None


# Main function to check the status of the service that will be called
def check_service():
    # pre-prepared list of reference nodes
    # for any network, it can be found on the website https://chainlist.org/
    list_of_public_nodes = [
        'https://polygon.llamarpc.com',
        'https://polygon.rpc.blxrbdn.com',
        'https://polygon.blockpi.network/v1/rpc/public',
        'https://polygon-mainnet.public.blastapi.io',
        'https://rpc-mainnet.matic.quiknode.pro',
        'https://polygon-bor.publicnode.com',
        'https://poly-rpc.gateway.pokt.network',
        'https://rpc.ankr.com/polygon',
        'https://polygon-rpc.com'
    ]
    
    # parallel processing of requests to all nodes
    with multiprocessing.Pool(processes=len(list_of_public_nodes)) as pool:
        results = pool.map(get_last_block_once, list_of_public_nodes)
        last_blocks = [b for b in results if b is not None and isinstance(b, int)]

    # define the maximum and median value of the current block
    med_val = int(np.median(last_blocks))
    max_val = int(np.max(last_blocks))
    # determine the number of nodes with the maximum and median value
    med_support = np.sum([1 for x in last_blocks if x == med_val])
    max_support = np.sum([1 for x in last_blocks if x == max_val])

    return max_val, max_support, med_val, med_support Now let's look at the main bot file . Since in different tasks you may only need alerting or only request instant values, I don't build a bot that can do everything at once, but instead I divide this functionality into different small examples. In this case, the main bot file code will only include alerting, but you can combine everything you need into one bot. alert_bot.py So, we import libraries and functions from the file above and set the necessary constants: import telegram
from telegram.ext import Updater
from functions import get_last_block_once, check_service

The address of the node, the state of which I'm tracking (also a public node in this case)
OBJECT_OF_CHECKING = 'https://polygon-mainnet.chainstacklabs.com'

Threshold for highlighting critical lag
THRESHOLD = 5

Your Telegram account ID. The easiest way to find out is through the @chatIDrobot bot
USER_ID = 123456789 Next, we describe a function that will be called regularly by the timer: def check_for_alert(context):

    # Call of the main function to check the network state
    max_val, max_support, med_val, med_support = check_service()
    # Call of the function to check the state of the inspected node
    last_block = get_last_block_once(OBJECT_OF_CHECKING)

    # Forming a message to be sent to Telegram
    message = ""
    # Information about the state of nodes in the external network (median, maximum, and number of nodes)
    message += f"Public median block number {med_val} (on {med_support}) RPCs\n"
    message += f"Public maximum block number +{max_val - med_val} (on {max_support}) PRCs\n"

    # this variable will store the decision whether to send an alert
    # in case the node is lagging or didn't respond
    to_send = False

    # state check
    if last_block is not None:
        out_text = str(last_block - med_val) if last_block - med_val < 0 else '+' + str(last_block - med_val)
        # Comparison with the threshold
        if abs(last_block - med_val) > THRESHOLD:
            to_send = True
            message += f"The node block number shift ⚠️<b>{out_text}</b>⚠️"
        else:
            message += f"The node block number shift {out_text}"
    else: # Handling the exception if the node didn't respond
        to_send = True
        message += f"The node has ⚠️<b>not responded</b>⚠️"

    # triggering the alert and sending a message to the user
    if to_send:
        context.bot.send_message(chat_id=USER_ID, text=message, parse_mode="HTML") Next, you only have to write the part where the bot is initialized and a regular job checking the node's state is connected to it: # Your Telegram bot token obtained through BotFather
token = "xxx"

# creating a bot instance
bot = telegram.Bot(token=token)
updater = Updater(token=token, use_context=True)
dispatcher = updater.dispatcher
job_queue = updater.job_queue

# Here, the interval variable (in seconds) sets the frequency
# of launching the check - in this case, every 10 minutes
job_queue.run_repeating(check_for_alert, interval=10.0 * 60.0, first=0.0)

#bot start
updater.start_polling() Next, the code can be run on any VPS server through: source ~/up_env/bin/activate
python uptime_bot.py Having previously configured the systemd unit-file. As a result, the bot operation will look as follows - if an alert has been triggered, I receive a message with the problem information: In the following article, I will describe how to implement the remaining task: Retrieve graphs based on the request, showing how everything has been progressing over the past X hours/days. It will consist of two parts: a script to log events triggered by cron and a bot that collects graphs from the logs based on user requests. The source code of the project is available in the GitHub . If you found this tutorial helpful, feel free to star it on GitHub, I would appreciate it🙂 repository Also published . here

How to Create a Telegram Bot for Monitoring Your Service Uptime in Python (Part 2/3: Alerting)

The date of Cavalier’s departure drew near

In this article, we are going to use Celery, RabbitMQ, and Redis to build a distributed Task queue. But what is a distributed task queue, and why would you build one? A allows you to offload work to another process, to be handled asynchronously (once you push the work onto the , you don’t wait) and in parallel (you can use other cores to process the work). distributed task queue queue So it basically gives you the ability to execute tasks in the background while the application continues to resolve other tasks. Use Cases of Task Queues The most basic and understandable example would be sending emails after the user is registered. In this case, you don’t know how much time it is going to take to send the email to the user, it can be 1ms but it can be more, or sometimes even not sent at all, because, in these case scenarios, you are not responsible or simply said you’re not aware of the task is going to be successfully done, because it’s another provider who is going to do that for you. So now that you got a simple idea of how you can benefit from the task queues, identifying such tasks is as simple as checking to see if they belong to one of the following categories: — The web app must serve users quickly without waiting for other actions to complete while the page loads, e.g., sending an email or notification or propagating updates to internal tools (such as gathering data for A/B testing or system logging). Third-party tasks — Jobs that are expensive in resources, where users need to wait while they compute their results, e.g., complex workflow execution (DAG workflows), graph generation, Map-Reduce like tasks, and serving of media content (video, audio). Long-running jobs — Jobs that you will schedule to run at a specific time or after an interval, e.g., monthly report generation or a web scraper that runs twice a day. Periodic tasks Setting up the dependencies for Celery requires a message transport to send and receive messages. Some candidates that you can use as a message brokers are: Celery RabbitMQ Redis Amazon SQS For this tutorial we are going to use , you can use any other message broker that you want (ex. Redis). RabbitMQ It’s also good to mention for what are we going to use now since for the message transporter we are using .When tasks are sent to the broker, and then executed by the celery worker, we want to save the state, and also to see which tasks have been executed before. For that, you’re going to need some kind of data-store and for this one, we are going to use Redis. Redis RabbitMQ For the result stores, we also have many candidates: AMQP, Redis Memcached, SQLAlchemy, Django ORM Apache Cassandra, Elasticsearch, Riak, etc To set up these services we are going to use docker as it’s easy to set up, it’s an isolated environment and you can easily reproduce the same environment when you have a configuration (Dockerfile or docker-compose). Project setup Let’s start a new python project from scratch. First let’s create a new directory, create all the files necessary for the project, and then initialize the virtual environment. mkdir celery-python && cd $_
touch __init__.py
touch tasks.py
touch docker-compose.yaml
touch requirements.txt

# create & activate the virtualenv

python -m venv env
source env/bin/activate Now let’s install the project . For this project, we are just going to need celery and Redis. requirements pip install celery redis Now it’s time to configure docker-compose to run RabbitMQ and Redis. In the docker-compose.yaml paste the following YAML configuration. Here we simply start up two services, by defining the image key to point to the image in , mapping the ports and adding environment variables. To see what types of environment variables you can use with your image, you can simply go to the corresponding image in dockerhub, and see the documentation. For example, you can check how to use RabbitMQ image . dockerhub host:docker here Now, let’s initialize the celery app to use RabbitMQ as a message transporter and Redis as a result store. In the tasks.py, let’s go ahead and paste the following code: I tried to keep the code as minimal as possible, so you can understand the purpose of this tutorial.As you can see, we have defined the URLs for RabbitMQ and Redis, and then we simply initialize the celery app using those configurations. The first parameter tasks is the name of the current module. Then we have decorated the function say_hello with @app.task which tells that the function is marked as a task, and then can later be called using .delay() which we will see in a bit. Normally we would have a module celery_app.py to only initialize the celery application instance, and then a separate moduletasks.py in which we would define the tasks that we want to run by celery. Build and run services with docker Now we only need to run the services (RabbitMQ and Redis) with docker. To run the images inside a container we simply run: docker-compose up -d This will take a while if you don’t have these images pulled locally. Then to verify that the containers are up and running we write: docker ps And you should see two services running, and additional information for each one, if not check the logs for any possible errors. Now let’s start the celery worker, and then let’s try to run some tasks with the python interactive shell. # Starting the Celery worker

celery -A tasks worker -l info --pool=solo This will run celery worker, and if you see the logs it should tell you that it has successfully connected with the broker. Now let’s run a task: # Running celery tasks

python
---------------------------------
Type "help", "copyright", "credits" or "license" for more information.
>>> from tasks import say_hello
>>> say_hello.delay("Valon")
<AsyncResult: 55ad96a9-f7ea-44f4-9a47-e15b90d6d8a2> We can see that we called the function using .delay() and then passed the name argument. This method is actually a star-argument shortcut to another method called . Then we see that we get back which is the task that was passed to the broker, and after that will get consumed and finished in the background by celery. apply_async() <AsyncResult If you look at your worker now, you will see in the logs that the worker received a task and then after 5 seconds will tell you that the task finished successfully. Now let’s run the same task but let’s put the results store in the game now. In the python shell let’s store the result in a variable, and then lets its properties. If we didn’t have the backend configured at the celery (Redis), we couldn’t access these properties or functions, because by default it wouldn’t store any state, but since we have it, we can see and get the pieces of information about our tasks. If you wanna dig deeper you can access your Redis database with a tool like TablePlus or you can set to monitor Redis and RabbitMQ. Flower As you can see in the image above, all the tasks are stored in Redis. Wrapping up In this article, we have set up a python application with Celery, RabbitMQ, and Redis from scratch. The purpose of the article was to show you what is task queue, what can we benefit from it, and how to implement it. The examples of the task are just for demonstration, but you can use the same configuration as I did on this one, adding tasks in the tasks module and the configuration in celery_app.py. See the docs . here I highly encourage you to use celery in your application as it is quite useful when you have things that take longer time, you need to schedule tasks, etc. If you read the article and found it useful don’t forget to like and share it with your friends & community. If you have any questions, feel free to reach out to me. Connect with me on 👉 , LinkedIn Github Also published . here

Creating a Distributed Task Queue in Python With Celery + RabbitMQ + Redis

If you just want to skip the tutorial and get the completed project, you can download it from https://tinyurl.com/rps-complete (You still need to update the to include your client SDK key). scripts.js Starter First, we need to set up the website we will be using Statsig on. The starter project can be downloaded from https://tinyurl.com/rps-starter, or you can follow the steps below. The following command creates the files we will need: touch index.html styles.css scripts.js In , paste the following: index.html <html lang="en">

<head>
  <link rel="stylesheet" href="styles.css">
  <script src="scripts.js"></script>
</head>

<body>
  <div class="container">
    <p id="computer-move-text">Pick a Move</p>
    <p id="result-text">...</p>
    <div>
      <button onclick="onPick(0)" class="button">✊</button>
      <button onclick="onPick(1)" class="button">🖐</button>
      <button onclick="onPick(2)" class="button">✌</button>
    </div>
  </div>
</body>

</html> In , paste the following: scripts.js let moves = ["✊", "🖐", "✌"];


function onPick(playerIndex) {
  const randomMove = moves[Math.floor(Math.random() * moves.length)];

  const cpuIndex = moves.indexOf(randomMove);
  const loseIndex = (playerIndex + 1) % moves.length;

  let result = "Won";
  if (cpuIndex === playerIndex) {
    result = "Tied";
  } else if (cpuIndex === loseIndex) {
    result = "Lost";
  }

  document.getElementById("computer-move-text").innerHTML =
    "Computer picked " + randomMove;
  document.getElementById("result-text").innerHTML = "You " + result;
} And in , paste the following: styles.css .container {
  transform: translate(-50%, -50%);
  position: absolute;
  left: 50%;
  top: 50%;
}

p {
  text-align: center;
  font-size: 32px;
  font-family: "Trebuchet MS", "Lucida Sans Unicode", "Lucida Grande",
    "Lucida Sans", Arial, sans-serif;
  font-weight: 700;
}

#result-text {
  font-size: 40px;
  font-weight: 900;
}

.button {
  outline: none;
  border: none;
  background: none;
  font-size: 60px;
  cursor: pointer;
  border-radius: 100px;
  padding: 10px 20px;
}

.button:hover {
  background-color: rgba(0, 0, 0, 0.133);
} If you now open the file in your web browser, you should see our basic Rock Paper Scissors game. As the player, you can select a move to throw and the computer will randomly select a move to play against you. Once a move has been picked, the page will update to display the result. index.html Adding Statsig Let’s now add Statsig so we can start experimenting with our RPS game. In our file, let’s include the Statsig JS SDK by adding a script import to our head tag. index.html <head>
  <link rel="stylesheet" href="styles.css">
  
  
  <script src="https://cdn.jsdelivr.net/npm/statsig-js@4.13.0/build/statsig-prod-web-sdk.min.js"></script>
  
  <script src="scripts.js"></script>
</head> Now in our file, we can add calls to the Statsig SDK. The following code uses the Statsig SDK we loaded from the JSDelivr CDN to make an that will fetch all data relevant to the given user Statsig’s servers. This initialize call hits the network and is asynchronous, so we must await it. scripts.js initialize let moves = ["✊", "🖐", "✌"];

(async () => {
  await statsig.initialize(
    "<CLIENT_SDK_KEY>",
    {
      userID: "some_user_id",
    }
  );
})();

function onPick(playerIndex) {

// ••• Now at the end of the function, let’s add a call to log that a game was played. The following code logs a event containing the result of the game. This will be the metric we are attempting to move in all upcoming experiments. If an experimental feature is “Good”, it should increase the volume of this metric as more people play. onPick logEvent game_played document.getElementById("computer-move-text").innerHTML = "Computer picked " + randomMove;
  document.getElementById("result-text").innerHTML = "You " + result;

  statsig.logEvent("game_played", result.toLowerCase()); // new line
} Now whenever a game is played, an event is logged with Statsig. We can verify this by going to the metrics page on console.statsig.com Running an Experiment We will now set up our first experiment to test new features added to our RPS game. Our first experiment will add new moves to the game in the form of Card Suits (♣️, ♥️, ♦️, ♠️). This doesn’t really make sense for an RPS game, but it will demonstrate how experimentation works. Create a Layer Login to console.statsig.com and we’ll add a new layer. If you haven’t already, you’ll need to create a project by selecting “Create New” in the top-left dropdown. Once you have a project, navigate to the experiments page by selecting “Experiments” from the left navigation list. When the page loads, select the “Layers” tab, and then create a new layer. We’ll call our new layer “rps_experiments”. Setup an Experiment On the Experiments page, with the layers tab selected, you can click “Create new Experiment in Layer“. Alternatively, from the Experiments page, with the experiments tab selected, you can click “Create”. Both approaches will display the experiment creation dialog, but the latter will require you to set the layer yourself. In the creation dialog, we’ll name our experiment “alternative_movesets”. Be sure that the layer field, below Advanced, is filled in with the layer we created above. With our experiment created, we can now add parameters to our layer and then select them as part of this experiment. We are going to set up a Test and Control group for this experiment. The Control will keep the same moves as we have currently, but the Test group will use card suits instead of hand signs. In the experiments page, select “+ Add Parameter” and add our new moves. They will just be an array of strings which are our card suit emojis. Once done, your setup should look similar to below. With Control just use the current ✊, ✋ and ✌️ and Test using the updated ♠️, ♥️, ♣️, and ♦️. Implement in Code Let’s update our so we can dynamically add the buttons at runtime. We’ll change the body to look like this, giving the buttons an id of "actions”. index.html div <body>
  <div class="container">
    <p id="computer-move-text">Pick a Move</p>
    <p id="result-text">...</p>
    
    <div id="actions"></div> 
  
  </div>
</body> Then we’ll update the file to pull the move set from Statsig and dynamically add the buttons to the DOM. The new setup function should look like the following. We first get a reference to our layer via and then get our moves by calling . The first argument is the name of our moves parameter and the second is a default value should the parameter not be found. scripts.js getLayer(“rps_experiments”) layer.get(“moves”, moves) let moves = ["✊", "🖐", "✌"];

async () => {
  await statsig.initialize(
    "<CLIENT_SDK_KEY>",
    {
      userID: "some_user_id",
    }
  );

  // -- new lines below

  const layer = statsig.getLayer("rps_experiments");
  moves = layer.get("moves", moves);

  const actions = document.getElementById("actions");

  // Dynamically add buttons to DOM
  moves.forEach((val, index) => {
    const button = document.createElement("button");
    button.textContent = val;
    button.onclick = () => onPick(index);
    button.className = "button";
    actions.appendChild(button);
  });

  // --

})(); Now if we reload the page, depending on what experiment group your user is in, you will either see no changes, or you will see the new moves displayed. If you don’t see any changes, change the userID until you get one that is in the “Test” group. You can also use a Feature Gate to override what group a given user is in, but that is beyond this tutorial (learn more ). here Extending the Experiment So we ran an experiment using but so far the flow hasn’t been that different from the API. Let’s add some more parameters to experiment with to show the power of . getLayer getExperiment getLayer Giving our Opponent a Name First, we’ll add a new parameter to our layer that will contain names to give to our AI Opponent. On our layers page (Experiments > Layers Tab > rps_experiments), add a parameter to the Layer by selecting “+ Add Parameter”. In the parameter creation dialog that appears, enter the values displayed below. Now, in our file, in the function, let’s add a call to our new parameter. We will reference the same layer as before, but this time our parameter name is “ai_name“. We will again provide a default value (“Computer“) to fall back to incase the parameter cannot be found. With our aiName fetched from the layer, we then update the DOM to use our new name. scripts.js onPick ai_name const aiName = layer.get("ai_name", "Computer"); // new line
document.getElementById("computer-move-text").innerHTML = `${aiName} picked ${randomMove}`; // updated Adding a Scoreboard Similar to our ai_name parameter, we will add a new score_board_enabled parameter to our layer. This time, however, we will use a simple boolean, instead of a string. Now, at the top of , we’ll add a new variable for holding our score. Then, in the function, we’ll increment the score on a win and display it in the DOM. We will use our scoreboard_enabled boolean to control whether or not this is displayed to the user. scripts.js onPick // Top of scripts.js

let moves = ["✊", "🖐", "✌"];
let score = 0; // new line // onPick function in scripts.js

function onPick() {

  // •••

  let result = "Won";
  if (cpuIndex === playerIndex) {
    result = "Tied";
  } else if (cpuIndex === loseIndex) {
    result = "Lost";
  } else {
    score++;
  }
  
  // •••

  // new lines added below
  if (layer.get("scoreboard_enabled", false)) {
    document.getElementById("scoreboard").innerHTML = "Your Score: " + score;
  }
} Running a Second Experiment Now with these new parameters, we can run another experiment (even if the first is still running) that contains the original moves parameter as well as the newer ai_name and scoreboard_enabled parameters. Because we are using rather than , we don’t need to update our code to explicitly reference the experiment, getLayer automatically returns the correct values depending on which experiment, if any, the user is in. getLayer getExperiment Similar to our previous experiment, we will go to the Experiments page and add a new experiment (Again, be sure to set our layer under Advanced > Add Layer > Layer). Let’s call this new experiment “updated_features”. rps_experiments For this experiment, we will create 3 groups (Control, Test_Pokemon and Test_AI). Control will be the same as before. Test_Pokemon will contain Pokemon-themed emoji and opponent. Test_AI will also have different emoji and opponent name, but will also display the scoreboard. This should result in the setup below. You can now run the updated_features experiment in parallel with the first alternative_movesets experiment. Depending on what group the user is in, they will be shown a different RPS game than other users. Change the userID if you wish to try out the different experiences. Evaluating the Experiments So our experiment has been running for a few days and it’s time to check on the results. Going to the Results tab on our updated_features experiment we can evaluate how our experiment did. We can see that 1.17K users have been exposed to our experiment. We have designated the game_played event as a Key Metric. Looking at the results, we can see that the Test Group “Test_Pokemon” has had a statistically significant lift. If this were a real feature, the Test_Pokemon group would be a clear ship.

VALON

valon.com

-- employees

Since n.d.

COMPANY RANKING

VALON

EVERGREEN INDEX #11096

Representing this company? Click here to claim and customize this page!

Valon WIKI

Apply to get your Tech Company News Page live on HackerNoon.com today!

VALON

valon.com

-- employees

Since n.d.

COMPANY RANKING

VALON

EVERGREEN INDEX #11096

RELATED COMPANIESRANK

STORIES ABOUT VALON

Representing this company? Click here to claim and customize this page!

Valon WIKI

Apply to get your Tech Company News Page live on HackerNoon.com today!