Inventors 
 
Copyright N°. 
 
 COPYRIGHT DEPOSIT. 
 
Hints to Inventors 
 
 TELLING WHAT INVENTIONS ARE NEEDED, 
 
 AND HOW TO PERFECT AND 
 
 DEVELOP NEW IDEAS 
 
 IN ANY LINES 
 
 Robert Grimshaw, Ph.D., M. E. 
 
 Author of " Steam Engine Catechism" "Pump Catechism," "Boiler Catechism, 
 
 "Engine Runners' Catechism" "Practical Catechism," "Locomotive 
 
 Catechism," "Shop Kinks," "Workshop Hints," "Preparing 
 
 for Indication," "Hints to Power Users," "Hints on 
 
 House Building," and numerous other 
 
 Practical Works 
 
 Second, greatly enlarged and revised, English Edition 
 
 Boston, Mass. 
 
 INVENTOR PUBLISHING CO. 
 
 1907 
 
JUL m 1W 
 
 / : -try 
 
 F^4 ,30,/ 967 
 
 
 
 Copyright, 1892, by Robert Grimshaw 
 Copyright, 1906, by Robert Grimshaw 
 Copyright, 1907, by Robert Grimshaw 
 
 All rights, including that of 
 translation, reserved 
 
DEDICATION 
 
 TO 
 
 JOHN E. SWEET 
 
 Formerly Professor of Mechanical Engineering, Cornell University; 
 Ex-President American Society of Mechanical Engineers 
 
 AS A HIGH TYPE OF THE 
 
 PATIENT, PERSISTENT, SYSTEMATIC, 
 PRACTICAL INVENTOR, 
 
 AND IN 
 
 SLIGHT RECOGNITION 
 
 OF HIS 
 
 ESTIMABLE PERSONAL QUALITIES 
 
Table of Contents 
 
 I. ELECTRICAL. 
 
 Electricity Direct from Coal. 
 Primary Battery. 
 
 Accumulator of the Energy of Lightning. 
 Galvanoplastic Deposits. 
 Cooking with Electricity. 
 Electrical Transmission of Power. 
 Electrical Incandescent Lamp. 
 Insulating-material for Wires. 
 Telephone Central Station. 
 Telephone Connections. 
 Telephoning at Sea. 
 Electrical Welding of Stern-posts. 
 Accumulators for Vehicles. 
 Paint for the Interior of Accumulator-boxes. 
 Abolishing the Odor of Accumulators. 
 Electric Deposition of Aluminium. 
 Telegraphic Writing and Drawing. 
 Substitute for Gutta-percha as an Insulating-medium. 
 Simple Electric Motors. 
 To Gild Sheet Aluminium Permanently. 
 Prevention of the Dangers of Alternating-current Trans- 
 formers. 
 
 [*] 
 
Table of Contents 
 
 II. CHEMICAL. 
 
 Continuous Distillation. 
 
 Vulcanization of Mineral Hydrocarbons. 
 
 Utilization of Vulcanized Rubber Scrap. 
 
 Bond for Emery-wheels. 
 
 Leather. 
 
 Russia Leather. 
 
 Dyes with Metallic Sheen. 
 
 Durable Aniline Dyes. 
 
 Artificial Diamonds and Pearls. 
 
 Artificial Mica. 
 
 Special Foods for Special Organs of the Body. 
 
 Remedy for Consumption and Cancer. 
 
 Artificial Tea and Coffee Flavors. 
 
 Removal of the Nicotin from Tobacco. 
 
 Sugar from Sorghum or Imphee. 
 
 Starch Sugar. 
 
 Matches. 
 
 Refined Cream of Tartar. 
 
 New Explosives. 
 
 Purification of River Water. 
 
 Odorless Petroleum. 
 
 Odorless Carbon Disulfid. 
 
 Dryer for Cottonseed Oil. 
 
 Cementing Metal to Glass. 
 
 Preserving Eggs. 
 
 Ice-machine. 
 
 Caneelling-ink for Postage-stamps. 
 
 Jet Black Writing-ink. 
 
Table of Contents 
 
 Copiable Typewriter-ink. 
 
 Indelible Marking-ink for Clothes. 
 
 Aniline Black. 
 
 Odorless Paint. 
 
 Utilization of Chlorate of Potash. 
 
 Pure Carbon. 
 
 Collection of Carbonic Acid from Fermenting Tuns. 
 
 Non-explosive Cooling Liquid. 
 
 Stain for Brass Goods. 
 
 Substitute for Sulfuric Acid in Shoe-blacking. 
 
 Durable Yellow Dye. 
 
 Solvent for Paraffin. 
 
 Substitute for Celluloid. 
 
 Odorless Asphalt. 
 
 Artificial Rennet. 
 
 Preventing Butter from Becoming Rancid. 
 
 Removal of Fusel-oil from Brandy and Whiskey. 
 
 Deodorizing Wood Vinegar. 
 
 Deodorization of Carbon Bisulfid. 
 
 Alloys of Aluminium. 
 
 Chemical Preparation of Yeast. 
 
 Material for Stamps. 
 
 To Make Soft Rubber More Durable. 
 
 Denatured Alcohol. 
 
 Manufacture of Calcium Carbid. 
 
 "Solid Alcohol." 
 
 Impregnation of Lumber. 
 
 Cheap Potassium Cyanide 
 
 Inodorous Petroleum. 
 
 Preserved Milk. 
 
8 Table of Contents 
 
 Edible Fat from Tallow. 
 
 Varnish for Violins. 
 
 Artificial Indigo. 
 
 Smokeless Gunpowder. 
 
 Cement for Porcelain and Glass. 
 
 Substitute for Glass for Optical Lenses. 
 
 Manufacture of Oxygen and Hydrogen. 
 
 New Alkaloids. 
 
 Thin Tough Flexible Paper. 
 
 Paper Pulp, 
 
 III. METALLURGICAL. 
 
 Manufacture of Aluminium. 
 
 Solder for Aluminium. 
 
 Obtaining Silver from Low-grade Ores. 
 
 Hardening Copper. 
 
 Gold from Brick Clay. 
 
 Recovery of Tin from Scrap-tinned Iron. 
 
 Direct Manufacture of Iron from the Ore. 
 
 Russian Sheet Iron. 
 
 New Steels. 
 
 Hardening the New Steels. 
 
 Malleable Pig Iron. 
 
 Regenerative Gas Stove. 
 
 IV. MINING. 
 
 Davy Lamps with Adjustable Flame. 
 
 Machine to Separate Graphite from Mica and Quartz. 
 
 Rock-drills. 
 
 Safety Device for Mining-cars. 
 
Table of Contents 
 
 Machine to Separate Slate from Coal. 
 
 Grapple for Boring-rods. 
 
 Machine for Cutting Coal in the Mines. 
 
 V. RAILWAYS. 
 
 Train-brake. 
 
 Train-stopper. 
 
 Heating-device for Railway-cars. 
 
 Station -indicator. 
 
 Rail-joint. 
 
 Iron or Steel Ties. 
 
 Snowplow. 
 
 Spark -catcher. 
 
 Car-lamp Lighter. 
 
 Hot-box Signal. 
 
 Switch-thrower. 
 
 Car-lighting. 
 
 Car-coupler. 
 
 Signal and Switch Thrower. 
 
 Signals in the Locomotive Cab. 
 
 Platform Scales for Weighing Cars in Motion. 
 
 Power Accumulator for Horse-cars. 
 
 Grip for Cable-cars. 
 
 VI. MARINE. 
 
 Boat-hull Model. 
 Fireproof Wood Covering. 
 Cellulose Filling Between Hulls. 
 Screw Propeller. 
 Water Ballast. 
 
10 Table of Contents 
 
 Feathering Paddle-wheel. 
 Jet Propulsion. 
 Naphtha Launch. 
 Storm Anchor. 
 Boat-disengaging Hook. 
 Lifeboat. 
 Harbor Dredge. 
 Gyroscope Attachment. 
 Steel Masts and Yards. 
 Riveting-machine . 
 Elastic Wire Rigging. 
 Varnish for Hulls. 
 Launching-way s . 
 
 VII. MILITARY. 
 
 Smokeless Powder. 
 
 Safety Device for Rifles and Revolvers. 
 
 Limber for Field Artillery. 
 
 Breech -loading Cannon. 
 
 Recoil Device for Field Artillery. 
 
 Air-gun as a Weapon. 
 
 Folding Writing-table. 
 
 Folding Camp-bed. 
 
 Army Tent. 
 
 Navigable Balloons and Aeroplanes. 
 
 VIII. MACHINE CONSTRUCTION. 
 
 Ball and Roller Bearings. 
 Adjustment for Ball Bearing 
 Screw -machine . 
 
Table of Contents 11 
 
 Grinding-machine for Railway Car-wheels. 
 
 Twist-drill with Oil-grooves. 
 
 Solder for Cast Iron. 
 
 Die Stocks. 
 
 Hydraulic Cranes and Hoists. 
 
 Micrometer. 
 
 Metal Setting for "Boart" Diamonds. 
 
 Safety Cranes and Hoists. 
 
 IX. MACHINE TOOLS. 
 
 Lathe for Cutting both Metric and Inch Pitches. 
 
 Grinding-attachment for Lathes. 
 
 Taper-turning Device for Lathes. 
 
 Attachment for Spherical Turning and Boring on the 
 
 Lathe. 
 Attachment for Planing Curved Surfaces. 
 Improved Radial Drill. 
 Radial Boring-attachment for the Drill -press. 
 
 X. RECORDING AND VENDING APPA- 
 RATUS, ETC. 
 
 Cash Register that Will Throw Out False Coins. 
 Small, Simple Cash Register. 
 Letter Scales. 
 
 Letter-registering Apparatus. 
 Liquid-vending Apparatus. 
 Time-recording Apparatus. 
 Newspaper-vending Apparatus. 
 Automatic Directory Device. 
 Calculating-machine . 
 
12 Table of Contents 
 
 XI. MISCELLANEOUS MACHINES. 
 
 Chain-making Machine. 
 Wood-bundling Machine. 
 Box-nailing Machine. 
 Brush-back Boring Machine. 
 Stone-dressing Machine. 
 Bone-crusher. 
 Bone-cleaner. 
 Intestine-cleaner . 
 Basket-weaving Machine. 
 Postage-stamp Sheet Perforator. 
 Wax Match Machinery. 
 Envelope Machine. 
 Pasteboard Tube Machine. 
 Coin-roll Filler. 
 
 XII. FOUNDRY. 
 
 Cleaning Process for Castings. 
 
 Casting-machine for Small Foundries. 
 
 Molding-machine . 
 
 Substitute for Sand for Molds. 
 
 Molding-material for Bronze Castings. 
 
 Casting under Pressure. 
 
 Process for Casting Silver. 
 
 Process for Casting Copper without Blow -holes. 
 
 Hardening Copper. 
 
 XIII. HEATING. 
 
 Oil Stove for Broiling. 
 
 Petroleum Fire-box for Kitchen Ranges. 
 
Table of Contents 13 
 
 Superheated Steam Oven. 
 Fuel Brikets. 
 Bond for Fuel Brikets. 
 Steam Meters. 
 
 XIV. LIGHTING. 
 
 Household Gas Machine. 
 
 Reliable Gas Meter. 
 
 Gas-pressure Regulator. 
 
 "Mantle" for Incandescent Gas-burners. 
 
 Device for Simultaneous Lighting of All the Burn* 
 
 ers in a Large Building. 
 Electric Arc Lamp. 
 Joint for Main Gas-pipes. 
 Electric Valve-closing Device. 
 Denaturing-material for Alcohol, 
 Safety Petroleum Lamp. 
 
 XV. STEAM BOILERS AND THEIR AP- 
 PURTENANCES. 
 
 Automatic Stoker. 
 
 Burning "Bagasse" 
 
 Smoke-consumer. 
 
 Firing with Coal-dust. 
 
 Safety Boiler. 
 
 Gage -glass. 
 
 Safety Device for Gage-glasses. 
 
 Safety Device for Live Steam-pipes. 
 
 Electroplating Boiler Interiors. 
 
14 Table of Contents 
 
 XVI. STEAM-ENGINE AND APPUR- 
 TENANCES. 
 
 Rotary Expansion Engine. 
 
 Reversible Steam Turbine. 
 
 Substitute for the Fly-wheel. 
 
 Safety Engine-stopping Device. 
 
 Safety Attachment for Sight-feed Oilers. 
 
 Governor. 
 
 Steam Road Wagon, 
 
 XVII. INTERNAL COMBUSTION MOTORS. 
 
 Gas Turbines. 
 
 Motors for Dirigible Balloons. 
 
 Alcohol Motor. 
 
 Street-car Motor. 
 
 XVIII. TRANSMISSION. 
 
 Reversible Flexible Shaft. 
 
 Speed-changing Device. 
 
 Substitute for the Stepped-belt Pulley. 
 
 Belt-stretcher. 
 
 Transmission Dynamometer. 
 
 Anti-friction Bearing. 
 
 XIX. POWER IN GENERAL. 
 
 Turbine Governors. 
 Solar Motors. 
 Power Accumulators. 
 
Table of Contents 15 
 
 XX. MOTOR CARS AND BICYCLES. 
 
 Anti-skidding Motor-car Tires. 
 
 Durable Motor-car Tires. 
 
 Benzin-tank Gage. 
 
 Sparking-apparatus . 
 
 Heavy Motor-car for Ordinary Roads. 
 
 Steering-apparatus . 
 
 Exhaust Muffler. 
 
 Power Meter. 
 
 Speed -indicator. 
 
 Speed-regulator. 
 
 Bicycle-lock. 
 
 Starting-gear Lock. 
 
 Dust-preventer. 
 
 XXI. STREETS AND ROADS. 
 
 Improved Roadway. 
 
 Monolithic Street Pavement. 
 
 Asphalt-leveler. 
 
 Substitute for Asphalt. 
 
 Paving-stone Rammer. 
 
 Paving -stone Remover. 
 
 Removal of Snow from Cities. 
 
 Street-sweeper. 
 
 Horse -shoe. 
 
 Wagon -wheel. 
 
 Safety Device for the Front of Tramcars. 
 
 XXII. BUILDING. 
 
 Brick -laying Machine 
 
16 Table of Contents 
 
 Scaffold. 
 
 Fireproof Paper Roofing. 
 
 Fire-escape. 
 
 Wall-papering Machine. 
 
 Lock for Hinged Shutters and Sash. 
 
 Roll Shutters for Shop Windows. 
 
 Roll Shades for Balconies. 
 
 Glazing without Putty. 
 
 Self-acting Window-closer. 
 
 Self-acting Door-closer. . 
 
 Device for Sliding Sash. 
 
 XXIII. KERAMICS AND GLASS-MAKING. 
 
 Brick Machine. 
 
 Long Terra-cotta Pipes. 
 
 Unglazed Colored Bricks. 
 
 Enamelled Building-bricks. 
 
 Brick Machine of the "Sausage," "Bar," or "Screw 
 
 Type- 
 Prevention of Shrinking of Clay. 
 To Free China Clay from Iron. 
 Glazing Pottery. 
 
 Manufacturing Lamp-chimneys of Glass. 
 Flexible Glass. 
 " Scotch " Gage-glasses. 
 
 XXIV. TEXTILE. 
 
 Utilizing Cactus Fiber. 
 Substitute for Horsehair. 
 Substitute for Broom Fiber. 
 
Table of Contents 17 
 
 Coating Cheap Fibers with Silk. 
 
 Substitute for Senegal Gum. 
 
 One-piece Umbrella-covering. 
 
 One-piece Reinforced Seamless Stocking. 
 
 Dry Process for Cleaning Cotton Lace. 
 
 Dust-removal. 
 
 Spinning Asbestos. 
 
 Spinning Moss. 
 
 Beaded Threads. 
 
 Sail-strengthener. 
 
 Fireproofing and Waterproofing Compound. 
 
 Photo-engraved Calico-printing Rollers. 
 
 Lace Loom. 
 
 Shuttle-changer for Looms. 
 
 Fish-net Machine. 
 
 Singeing-machine . 
 
 XXV. WRITING-APPLIANCES. 
 
 Improved Typewriting-machine. 
 
 Machine for Writing in Books. 
 
 Machine for Writing Music-note Characters. 
 
 Electric Drive for the Typewriter. 
 
 Variable Impression for the Typewriter. 
 
 Variable Carriage-feed for the Typewriter. 
 
 Noiseless Typewriting-machine. 
 
 Duplicating-apparatus. 
 
 Hektograph Ink. 
 
 Fountain pen. 
 
 Indelible Stamp-cancelling Ink. 
 
 Red Pencil. 
 
18 Table of Contents 
 
 XXVI. PRINTING. 
 
 Typesetting-machines . 
 
 Half-tone Printing-press. 
 
 Ink-distributing Roller. 
 
 Multicolor Printing at One Impression. 
 
 Printing on Sheet Metal. 
 
 Light Non-inflammable Printing-blocks. 
 
 Printing-types. 
 
 Process for Making Border Plates. 
 
 Black-bordering Machine. 
 
 Artificial Lithographic Stone. 
 
 Lithographic Printing-ink. 
 
 Black Copiable Printing-ink. 
 
 Rapid Stereotyping Process. 
 
 XXVII. PHOTOGRAPHY. 
 
 Telephot Objective. 
 Lens-grinding Machine. 
 Blocking Photo-engravings. 
 Half-tone Photo-engraving Process. 
 Light-printing Process. 
 Photographic "Black Prints." 
 Photography in Colors. 
 Developing and Fixing Bath. 
 
 XXVIII. AGRICULTURAL. 
 
 Mowing-machine for Sugar-cane. 
 
 Hop-picker. 
 
 Cotton-picker. 
 
Table of Contents 19 
 
 Cotton -bale Tie. 
 Milking-machine . 
 Incubator. 
 Caterpillar-destroyer. 
 Peach-blossom Thinner. 
 
 XXIX. FLOUR MILLING. 
 
 Bran Packer or Baler. 
 Artificial Millstone. 
 Bleaching Wheat Flour. 
 
 XXX. HOUSEKEEPING APPLIANCES. 
 
 Preserving-can. 
 
 Spring Shade-rollers. 
 
 Carpet-nails. 
 
 Household Emery-wheel. 
 
 Bread-cutting Machine. 
 
 Egg-box. 
 
 Time Device for Egg-cooking. 
 
 Copper-plated Sheet Steel Utensils. 
 
 Button -sewing Machine. 
 
 Household Filter. 
 
 Floor-scrubbing Machine. 
 
 Floor-covering. 
 
 Sewing-machine to Use Wooden Spools. 
 
 Ice-cutting Tool. 
 
 Oyster-opening Machine. 
 
 Knife-sharpening Device. 
 
20 Table of Contents 
 
 XXXI. IN MUSICAL LINES. 
 
 Finger-limbering Device. 
 Sheet-music Turner. 
 Impromptu Registering-device. 
 Semi-automatic Piano-playing Apparatus. 
 Disk-shifter for Automatic Musical Instruments. 
 
 XXXII. MISCELLANEOUS. 
 
 Fire Hose. 
 
 Street Letter-box Lock. 
 
 Reservoir Lettering-brush. 
 
 Device for Preventing Horses from Bolting. 
 
 Flexible Glass. 
 
 Utilization of Peat. 
 
 Carbonizing Peat. 
 
 Utilization of Sawdust. 
 
 Biograph. 
 
 Folding Opera-glasses. 
 
 Anemometer. 
 
 Pyrometer. 
 
 Patella-holder. 
 
 Air-tight Watch-case. 
 
 Securing Toothbrush Bristles. 
 
 Disinfecting-apparatus for Razors. 
 
 Non-alcoholic Beverage. 
 
 Utilization of Animal Offal. 
 
 Removing Deposit from Port-wine Bottles. 
 
 Hairpin that Will Not Fall Out. 
 
 Self -threading Needle. 
 
Table of Contents 21 
 
 Cigar-lighter. 
 
 Cigar-holder. 
 
 Air-tight Metal Capsule for Bottles. 
 
 Umbrella-stick. 
 
 Skate. 
 
 Cremation-furnace . 
 
 Head -covering . 
 
 Foot-gear. 
 
 Newspaper-holder . 
 
 Case-binding for Books. 
 
 Envelope that Cannot Be Opened. 
 
 Automatic Janitor. 
 
 Sensitive Cornet. 
 
 Machine for Picking the Bones Out of Shad. 
 
 These last three are not proposed in earnest, but merely 
 to end the dry list pleasantly. 
 
 XXXIII. INVENTIONS FOR WHICH 
 PRIZES ARE OFFERED. 
 
 Protection from High-tension Electric Currents. 
 Safety Hoisting-appliance. 
 Safety Appliance for Mine-cars. 
 Dust-collector for Rag-sorting Rooms. 
 Dust-collector for Hemp-carding Rooms. 
 Dust-collector for Cement Works. 
 Prevention of Collisions at Sea. 
 Ship-saving Device. 
 Passenger-saving Device. 
 Destruction of Flies. 
 
22 Table of Contents 
 
 Portable Field Kitchen. 
 
 Construction and Operation of Railways. 
 
 Engines and Rolling-stock. 
 
 Railway Management. 
 
 Mechanical Stoking of Locomotives. 
 
 Steam-heating of Trains. 
 
 Air-brake Hose. 
 
 Communication between Different Members of the 
 
 Train Crew. 
 Motor-car Trains. 
 Traffic Distribution. 
 Two -story Cars. 
 Car-door Locking-device. 
 
 XXXIV. PERFECTING AND DEVELOPING. 
 
 XXXV. SELLING PATENTS. 
 
 XXXVI. MUD-GUARDS FOR AUTO- 
 MOBILES. 
 
 XXXVII. INVENTION NEEDED BY THE 
 FRENCH GOVERNMENT. 
 
Introduction to the First Edition 
 
 This volume is to some extent a repub- 
 lication of articles of the author, .some of 
 which appeared in the Sunday World, and 
 others in the Practical Mechanic, and which 
 were intended to do inventors a twofold 
 service: first, to warn them from fields in 
 which remuneration was not likely to come 
 from inventions, because either the art was 
 so well advanced, or there would not be 
 sufficient demand for even a perfect inven- 
 tion; second, to point out lines in which in- 
 ventions are greatly needed, and in many 
 cases loudly demanded, hence should pay. 
 
 In the publications named the author 
 gave quite a number of hints which pre- 
 sented themselves to him in the course of 
 his perambulations and thinking-fits; and 
 since then there have come up about as 
 many more, which it would be well for him 
 (and her also) of ingenious mind and prac- 
 tical training to produce. 
 
 In looking over the broad field of indus- 
 
 [23] 
 
24 Introduction 
 
 try the intelligent observer is struck with 
 two things: first, the high degree of pecu- 
 niary reward which has been attained by 
 those inventors who have gone to work to 
 supply something that the world needed; 
 second, the great number of lines in which 
 there is still opportunity for inventors to 
 succeed. 
 
 The mere fact that there is already a 
 successful machine or process in use need 
 not deter an inventor from making a better 
 one. The history of the sewing-machine, 
 the typewriter, the mower and the reaper, 
 and a hundred other inventions, shows that 
 when people are once aroused to the desir- 
 ability of having a thing done better than 
 before they are greedy for still more and 
 further progress. Every invention cannot 
 or will not be that which is brought out first. 
 The rest have a good show, and sometimes 
 a better one, by reason of what has been 
 done by the pioneer. The author would say 
 to every inventor ,whether or not yet success- 
 ful, Keep on inventing; only be sure to 
 get up things which are needed, and do not 
 waste your time in converting people to 
 
Introduction 25 
 
 the idea that what you have invented is 
 what they want. If they do not know that 
 they want a thing, and do not call for it, 
 never mind about producing it as long as 
 so many things are still unfurnished which 
 they do want, know that they want, and 
 for which they keep on calling. 
 
 New York City. 
 
Introduction to the Second 
 American Edition 
 
 This edition, published many years after 
 the first (now out of print), is so long delayed 
 because since a short time after the appear- 
 ance of the first the author has lived almost 
 uninterruptedly in Europe, where he has 
 been much too busy to prepare for Amer- 
 ica more than the most necessary literary 
 work. In the last few years, however, he 
 has put out two editions of a similar Ger- 
 man work. The first of these, " 300 Winke 
 fur Erfinder," was a much augmented 
 translation of the original American one; 
 the second, "450 Winke fur Erfinder," is 
 still further enlarged by numerous valuable 
 suggestions in response to letters and post- 
 cards to important representative Euro- 
 pean firms, asking if there were in their 
 various respective lines any inventions 
 which they regarded as desirable. From 
 time to time, also, inquiries for machines, 
 processes, and products have reached him 
 
 [26] 
 
Introduction 27 
 
 from "God's country." Nearly all of these 
 are here embodied. Some of the inquirers 
 for special inventions have already been 
 notified that what they called for stood at 
 their disposition. Many of the problems 
 posed have been solved. Most of them are 
 capable of more than one, some of them 
 even of several, both technically and com- 
 mercially practical solutions. 
 
 The author will be glad to give his read- 
 ers, at any time, whatever information is in 
 his power concerning inventions already 
 matured, or possible markets for properly 
 protected ideas. He begs to be excused, 
 however (in view of the great number of 
 insufficiently prepaid letters addressed to 
 him from America), for remarking that let- 
 ters requiring an answer should enclose a 
 five-cent stamp for reply, and be prepaid at 
 the rate of five cents for each quarter of an 
 ounce of their weight, and that short-paid 
 letters and unpaid packages will be refused, 
 
 Hannover, Germany, September, 1906. 
 Fundstrasse 30. 
 
Chapter I. 
 ELECTRICAL* 
 
 Of course the first lines in which there appear to 
 be opportunities for successful invention are those 
 in which electricity and its myriad appliances are 
 made to do man's bidding. 
 
 One of the greatest of all electrical problems that 
 is just now offered for solution is the production of 
 electricity direct from coal without the intervention 
 of a steam boiler and engine; without the incidental 
 production of light and heat. Whoever does this 
 successfully should become " rich beyond the dreams 
 of avarice." This may call for the production of a 
 primary battery which shall use ordinary coal as 
 one of its electrodes, oxidizing this perfectly to car- 
 bonic acid, without the production of heat — and 
 all at a cost which will render such production of 
 electrical current a commercial rival with the pres- 
 ent method of using the coal in a furnace to produce 
 steam with which to run an engine by which to turn 
 a "dynamo" which shall evolve the current. 
 
 The storage battery or secondary battery — par- 
 ticularly for vehicles — is far too heavy, compli- 
 cated, costly, and liable to deterioration, and gives 
 
 * See also the chapter "Inventions for which Prizes Are 
 Offered." 
 
 [29 ] 
 
30 Hints to Inventors 
 
 off fumes which do not commend it to popular ap- 
 proval. There is ample opportunity for inventors to 
 do good and paying work here. 
 
 If some scientist — or any one, in fact — will in- 
 vent a way of storing up lightning and using it when 
 and where it is needed, he will make for himself 
 more than a mere name. 
 
 Electro-deposition needs looking into. There 
 are several metals which as yet cannot very well be 
 deposited by the galvanic current; and the art of 
 depositing alloys has as yet but very limited prac- 
 tical application. 
 
 Electric cooking has been but little more than 
 suggested. In many houses now having electric 
 lights a good device for cooking by electricity taken 
 from the same wires which supply the light could 
 very readily be introduced. 
 
 The problem of electric transmission of power 
 has been solved by several methods, more or less 
 (generally less) satisfactory. This field is a wide 
 one, and the incentive to effort very great. 
 
 Can you make a better filament for the incandes- 
 cent electric light than those which you see? Or 
 can you even make as good a one ? If so, you can 
 practically dictate your own terms for the sale of 
 your patent. 
 
 There is a big demand all over the country for an 
 insulating-material for wires which would be light, 
 cheap, easily handled, and not readily altered or 
 attacked by heat, cold, dampness, acids, alkalies, 
 
Electrical 31 
 
 coal-gas, or sewer-gas, and which would also resist 
 abrasion. 
 
 A telephone exchange in which each subscriber 
 could catch and hold any other in the system with- 
 out resort to "Central" is not so impossible of pro- 
 duction as might at first seem. 
 
 Those who have spent a half-hour or so trying to 
 ring up a man at the other end of a telephone line 
 and have found out after much effort that there was 
 no one there would feel better if there was on the 
 market something which would at once, when a box 
 was rung up, give a signal stating that there was no 
 one to receive a message and would not be until a 
 time which would be stated by the attachment. 
 
 Long-distance telephoning is only in its infancy. 
 There is need of greater certainty of working and of 
 greater clearness of sound. 
 
 Telephoning and telegraphing at sea may seem 
 wild. So did sending a message along through a 
 wire without pulling the wire. There are people 
 now living who will send a telegraph from one ves- 
 sel at sea to another; or to port. 
 
 [The above was written in 1891 and published 
 then in newspaper form; in 1892 it appeared in the 
 first English edition of this work. Since then, Mar- 
 coni, d'Arco, Slaby, and others have wrought won- 
 ders in long-distance wireless telegraphy. Wire- 
 less telephoning at long distances seems now (Au- 
 gust, 1906) still among the unsolved problems.] 
 
32 Hints to Inventors 
 
 How long will it be before the stern-posts of great 
 steamships will be made by electric welding ? [Ther- 
 mit welding of such pieces seems a great success.] 
 
 Up to date the electric accumulator — and es- 
 pecially that offered for use on carriages and power 
 bicycles and tricycles — is by far too heavy, compli- 
 cated, expensive, short-lived, and evil-smelling. Here 
 is an excellent chance for inventors to solve a prob- 
 lem that has not engaged as much attention as it 
 deserves. 
 
 The much-desired accumulator must be suitable 
 for street-railway purposes, and be able to be de- 
 veloped for the use of interurban railways. The 
 overhead system, although offering the great advan- 
 tage of cheapness of original outlay and of main- 
 tenance, is very unwelcome to fire departments and 
 insurance companies, as, not satisfied with being a 
 source of fire, it is a great hindrance to the use of 
 fire-ladders; so that despite its cheapness, simplic- 
 ity, lightness, and rapidity of construction and re- 
 pair, it must eventually go "where the woodbine 
 twineth." But its successor must pass a much more 
 severe examination than is usual with inventions 
 offered for public acceptance. The desired accumu- 
 lator must be much lighter than its predecessors 
 that have been tried in public; must not lose its 
 liquid contents by reason of the inevitable shaking 
 that it will undergo on the average track — to say 
 nothing of ordinary roads if it is used for road ve- 
 hicles; must emit no gases that are dangerous to 
 
Electrical 33 
 
 life or property, or even unpleasant to the passen- 
 gers; and it must not take so much time in loading 
 as the present ones. Its units must not be so large 
 or so heavy that they will be difficult to handle, as 
 in changing at the end of a trip. In several types 
 the jarring of service shakes the compound from be- 
 tween the plates and thus ruins the cells. This is 
 of course to be got around — most easily, perhaps, 
 by using horizontal plates. Further: the new ac- 
 cumulator must not be freezable even in a North 
 Canadian temperature; and, finally, it must not re- 
 quire the attendance of Lord Kelvin, Herr Kapp, 
 or other world-wide celebrity to keep it in good con- 
 dition. 
 
 A paint for the interior of accumulator-boxes is 
 still among the desirable things in electrical lines. 
 It must be highly resistant to sulfuric and nitric 
 acids, and other chemicals used in filling the accu- 
 mulator, and be easily put on. 
 
 It is quite possible that, while the accumulator of 
 the future will replace the overhead wire conductor 
 system, there will for a long time yet be experi- 
 ments made as regards underground conductors for 
 power, and especially for interurban railways. This 
 would effect a saving in fuel, lubricant, wages, and 
 interest on permanent way and rolling-stock. 
 
 But the new underground conductor must be 
 much better than the present ones. The system 
 must be able to be used alone and in combination 
 with steam traction, not only where the latter is used 
 
34 Tips to Inventors 
 
 on connecting lines, but where the service is mixed 
 electric and steam. That means that the new sys- 
 tem must not require a special track, but the trains 
 with steam traction must use the same rails. 
 
 It must be of such simplicity and character that 
 it can be introduced on a line already having steam 
 traction, without interfering with either the local 
 or the through traffic, at least as regards the passen- 
 ger traffic, even for a few hours ; and its introduction 
 must not interfere much even with the freight traf- 
 fic. The desired system must be neither expensive 
 nor complicated. By this the author means that it 
 must not be necessary, as is the case with one sys- 
 tem seriously proposed some time ago, to have an 
 iron pot every yard or so along the track, filled with 
 magnets and complicated mechanisms. If such 
 contrivances be necessary, they must not be nearer 
 together than at present is the case with the rail- 
 joints — say every thirty feet. The system must 
 not be interfered with by snow, overflows, or rain, 
 and must be so simple that an ordinary workman 
 can put it in order and make slight repairs thereon, 
 without special appliances that cannot be carried 
 in an ordinary handbag During tests and exper- 
 iments and the carrying-out of light improvements 
 the traffic must not be disturbed — with the excep- 
 tion of reaches of track not more than four rails 
 long. The rail- joints must be of such character that 
 no sawing, planing, or filing is necessary on the track 
 itself; all such work must be done in the rail-mill, 
 
Electrical 35 
 
 or in some shop, ready for the rails to be laid and 
 joined. If possible, the rails and fish-plates should 
 not be different from those used for steam traffic 
 on the same road. Further: the entire system must 
 not make any complications with the telegraph or 
 telephone system, or with the electric handling of 
 switches or signals. A further condition is that the 
 system shall be unaffected by lightning and that it 
 shall offer no special danger to human fife or to 
 property, even when struck by lightning. The plant 
 and connections must be durable, and the annual 
 repair-bills fight. Spare parts must be cheap and 
 easily obtained and inserted; and be so light that 
 they can be carried on the repair-car. These spare 
 pieces must be "standard," — that is, the same for 
 all lines, — so that if two different lines come under 
 the same management after being equipped, repairs 
 will not be unduly complicated by the necessity of 
 having on hand two sets of stock. 
 
 The only way in which it seems possible to arrive 
 at such a perfected system is for the different rail- 
 way managements to combine and build an exper- 
 imental track on which tests can be made under 
 experts paid by such combined management — just 
 as the various electric companies in Europe have 
 formed a " Studiengenossenschaft" to test, at joint 
 expense, various methods of rapid electric trac- 
 tion. 
 
 As yet the electro-deposition of aluminium on 
 other metals, as well as that of other metals on al- 
 
36 Hints to Inventors 
 
 uminium, has not been accomplished to the satis- 
 faction of those most interested. 
 
 A very desirable process would be one by which 
 aluminium could be permanently and satisfactorily 
 electroplated with pure gold. 
 
 An apparatus for the transmission of facsimile 
 writing and drawings would be welcome to all news- 
 paper publishers, as well as to the police, as it would 
 be capable of sending sketches of localities and por- 
 traits of criminals or celebrities. It would be espe- 
 cially desirable to be able to use this apparatus in 
 connection with the ordinary telephone conductors. 
 Steps in this direction have already been made, but 
 up to this writing — August, 1906 — there has been 
 nothing offered the buying public; capitalists are 
 about the only ones as yet who have cognizance of 
 the inventors' progress — and failures. 
 
 Gutta-percha — which is quite a different thing 
 from caoutchouc — has as an isolating-material for 
 electricity the very undesirable quality that it softens 
 by heat, so that copper wires insulated therewith in 
 cables and more simple conductors do not remain 
 central. As this material is dear, and gets dearer 
 every year, and as this is also the case with India 
 rubber, it is desirable to find therefor a cheap and 
 efficient substitute. 
 
 The electromotors which are offered for use by 
 the average power-user run, for most purposes, too 
 fast. Besides the need of slower ones, there is room 
 for small ones, as well made as the large ones, which 
 
Electrical 37 
 
 will deliver from 1-50 up to 1-20 horse-power, and 
 which have controllable speed. They should, for 
 the present at least, be wound for the ordinary 
 110- volt current found in the usual household light- 
 ing-system. 
 
 For the best manner of avoiding the danger of 
 touching a high-tension conductor by a low-tension 
 wire, in the case of transmission by alternate cur- 
 rent, prizes are offered by the dynamo-manufactur- 
 ers and others most concerned. 
 
Chapter II. 
 CHEMICAL 
 
 The problem of the continuous fractional distil- 
 lation of petroleum often has been offered to all 
 those who should be most interested in its accom- 
 plishment as a very desirable one to solve. At pres- 
 ent, a still is filled and made to yield so much of one 
 compound, then so much of another, and so on un- 
 til it is empty, when it must be cooled and recharged. 
 What is wanted is a still or apparatus which will 
 work as a flour-mill does, — receive constant feed of 
 raw material and deliver constant streams of the va- 
 rious products and by-products. 
 
 There are many mineral hydro-carbons which it 
 would pay to "vulcanize" as India rubber and gutta- 
 percha are now. 
 
 What is not known about "vulcanizing" India 
 rubber, gutta-percha, and other similar substances 
 would fill a large volume. Get up a process for re- 
 covering India rubber out of old vulcanized articles, 
 and another for vulcanizing the material so that it 
 will not get soft by heat nor brittle by cold. 
 
 In the manufacture of emery-wheels, a bond is 
 desirable which will possess the advantages of both 
 India rubber and silicate. 
 
 Can you make leather which shall be as pliable 
 [38] 
 
Chemical. 
 
 as ordinary leather and shall wear as well as raw- 
 hide ? If so, you can borrow money on the process. 
 
 We cannot yet imitate Russia leather cheaply 
 and well. Inventors take note. 
 
 The metallic sheen which is seen on liquid aniline 
 colors, and which seems at times to be such an ob- 
 jection, should be taken advantage of. Inventors 
 should aim to produce fabrics having various col- 
 ors and a metallic lustre. 
 
 The chemist who can make aniline dyes perma- 
 nent will confer a great boon upon the community 
 and should line his pockets well with bank-notes. 
 
 In the manufacture of artificial precious stones 
 the French have done a good deal; but for the in- 
 ventor to have the right to be proud, the diamond 
 and the pearl should be made as successfully as the 
 turquoise and the ruby. 
 
 The chemist who will produce an artificial mica 
 in large sheets will find buyers waiting for his patent 
 or process. 
 
 The discovery of special foods for special parts 
 of the body, in like manner as now applied for differ- 
 ent crops, is worth seeking. 
 
 The dread disease pulmonary consumption, and 
 that other equally fell destroyer, cancer, have never 
 been subdued by specifics, and whoever produces 
 medicaments which will cure them will deserve well 
 of his fellow men, and should reap a fortune. 
 
 Some time when you have leisure produce an arti- 
 ficial coffee or tea flavor which shall be as like the 
 
40 Hints to Inventors 
 
 real as artificial vanilla is like the flavor which it 
 imitates. 
 
 Can you take the nicotin out of tobacco with- 
 out injuring the other flavoring principles which it 
 contains ? If you can you will be a benefactor any- 
 how, and perhaps a millionaire. 
 
 Why don't you invent a good process for making 
 sugar from sorghum or imphee ? 
 
 Sugar (that is, saccharose) from starch" will come 
 some day — when we know how to produce it. 
 Whoever finds out ought to get rich. Making glu- 
 cose from starch has paid handsomely, but making 
 sugar from the same substance should enrich inventor 
 and manufacturer. 
 
 Match-making needs a little impulse. Can you 
 get up a fusee which will not blow out and which 
 will not smell like a drug-store on fire? 
 
 A cheaper process of making pure cream of tartar 
 than those at present employed should bring wealth 
 to its inventor. 
 
 There is always a good chance for new explosives, 
 particularly if they are controllable and make no 
 noxious gases. 
 
 A process by which the water of great rivers may 
 be purified more rapidly than by filtering-beds should 
 command attention and a high price. 
 
 Can you take all the smell out of kerosene-oil? 
 If so, you know how to do what many manufactur- 
 ers have been trying to do for a long time. 
 
 The chemist who will make from cottonseed 
 
Chemical 41 
 
 either a drying or a non-drying oil should not want 
 for cash if he manages his affairs properly. 
 
 More cements for fastening metals to glass would 
 find room and sale. 
 
 No one seems to have been able, as yet, to pre- 
 serve eggs fresh and sweet for a long time, as fruits 
 are kept. Some one will manage it some day and 
 reap a reward therefor. 
 
 Inventors should get at the matter of the manu- 
 facture of artificial ice. What is needed is a machine 
 which will make ice, first, safely; second, cheaply; 
 and third, without using chemicals which have to 
 be imported. 
 
 A good indelible canceling-ink for postage-stamps 
 has been the aim of inventors and the desire of the 
 post-office authorities for many years, but has not 
 as yet made its appearance. When it comes it will 
 not have to create a demand ; the demand is already 
 here. 
 
 A jet-black ink which will be black when written 
 with, will stay black, will not corrode a steel pen, 
 and will flow freely is one of the things that every- 
 body wants. 
 
 A copiable typewriter ink, that will be black after 
 copying as well as before, is desired. 
 
 There is as^yet no decent aniline black color. 
 There are blacks which show through them a green 
 or a brown or a blue color, and others which are 
 even bronze when the light falls upon them a cer- 
 tain way; but the real "black black" is not on the 
 market, nor even on the road to the market. 
 
42 Hints to Inventors 
 
 The so-called "indelible" ink for marking linen 
 seems to live up to its name only when the articles 
 marked therewith are washed at home. Directly 
 the laundries get hold of the clothes the ink-marks 
 disappear, and usually with them the cloth where 
 they were. A black writing-ink which would with- 
 stand the severe bleaching-materials used in the 
 laundries would sell well. 
 
 It would seem as though whoever got out an odor- 
 less house-paint that would cover well and not dis- 
 integrate under the influence of the weather would 
 find it very easy to dispose of. 
 
 There seems to be insufficient field for the utiliza- 
 tion of chlorate of potash. 
 
 Nearly pure carbon — say 99.5 per cent — in 
 large blocks would find ready sale. 
 
 A simple manner of collecting the carbonic acid 
 generated in the fermentation of brewers' and dis- 
 tillers' mash would find ready sale. The consump- 
 tion of the gas in compressed form is already large, 
 and is rapidly increasing. 
 
 For use in the ice and cold brine machines in 
 breweries, cold-storage warehouses, etc., there would 
 be a ready market for a liquid that was inexplosive 
 and not suffocating in gaseous form, and would not 
 attack iron. 
 
 Brassware manufacturers seek a coloring-liquid 
 which will blacken the finished goods while keep- 
 ing them "matt." The manufacturers of micro- 
 scopes, opera-glasses, surveyors' instruments, etc., 
 need such a material daily. 
 
Chemical 43 
 
 As a rule, blacking for men's shoes contains acid 
 and eats the leather. A blacking which would yield 
 a real black with a high polish and contain some 
 harmless substance to replace the sulfuric or acetic 
 acid now used ought to take well when once beyond 
 the probation stage. 
 
 If we observe the real Gobelin tapestry we will 
 see that the original greens and yellows have 
 faded proportionately much more than the other 
 colors. In some originally very valuable pieces these 
 two colors have entirely disappeared. This is be- 
 cause the yellow dye used at the time of manufac- 
 ture of the original Gobelin work was not perma- 
 nent; nor is there yet on the market one good per- 
 manent yellow dye for textiles. 
 
 Paraffin wax is a very useful material, especially 
 in rendering vessels water-tight, but has the disad- 
 vantage of being combustible. A solvent therefor, 
 which would produce a solution that was uninflam- 
 mable, would be of great use in the industries — as 
 for instance in the manufacture of dry batteries. 
 
 Celluloid is a very useful material, which has 
 worked its way by sheer worth into thousands of 
 articles of daily consumption, and has produced 
 large sums for its inventor and manufacturers. It 
 has, however, three very great disadvantages: it is 
 highly — even dangerously — combustible, requires 
 in its manufacture camphor (which is getting dearer 
 every day), and smells of this latter substance. Sev- 
 eral materials have been offered as substitutes for 
 
44 Hints to Inventors 
 
 the celluloid, no one of which, however, replaces it 
 for more than a few of the many purposes for which 
 celluloid is used. Milk is the raw material of one 
 of these; potato pulp, that of another. The indus- 
 trial chemist could find few better fields in which 
 to work. 
 
 Asphalt, used so universally for street-paving 
 (where dishonest contractors do not substitute the 
 much less desirable coal-tar), has a very disagree- 
 able smell which it would be a good idea to elimi- 
 nate. 
 
 Artificial rennet for the manufacture of cheese 
 would sell well. It would also find application in 
 the household. 
 
 To prevent butter from becoming rancid, with- 
 out causing it to lose its characteristic taste, odor, 
 and color, or injuring its digestibility, would be a 
 problem worthy the chemist's attention. 
 
 The presence of fusel-oil (largely composed of 
 amylic alcohol) in brandy, and more especially in 
 whiskey (that made from potatoes is the worst in 
 this respect), is most undesirable, as the taste is un- 
 pleasant and the so-called "oil" is poisonous. Dis- 
 tillers seek a suitable process by which its presence 
 may be prevented in the distilled spirit, or if that 
 cannot be accomplished, by which it may be re- 
 moved without great trouble and expense, or with- 
 out the expenditure of too much time in "ripening." 
 
 Vinegar made from wood has a most unpleasant 
 taste; and while this does not prevent its being used 
 
Chemical 45 
 
 in many industries, it shuts it almost completely 
 out of household use. It is very well worth deodor- 
 izing. 
 
 Carbon disulfid, used in the manufacture of In- 
 dia-rubber goods, has the advantage of being the 
 best known solvent of caoutchouc, and the disad- 
 vantage of having a most disgusting smell. This 
 latter quality shuts it out of use for many indus- 
 trial purposes — to say nothing of its application 
 in the household as a solvent of grease. Who will 
 render it inodorous ? 
 
 For many industrial chemical purposes aluminium 
 cannot be used, as it is attacked by many of the acids 
 in the chlorine series, many of which contain more 
 or less nitric acid as impurity. Here there are two 
 ways out of the difficulty : either to produce an alu- 
 minium alloy that would not be attacked by these 
 acids, or to invent a process by which the acids may 
 be produced on an industrial scale, free from nitric 
 acid. 
 
 Who will invent a process by which ordinary 
 brewers' yeast shall be produced as a mass which 
 shall be free from the taste and smell of beer (pref- 
 erably white in color) and can be compressed into 
 cakes and wrapped in tin-foil for bakers' and house- 
 hold use ? The product must preserve its ferment- 
 ing-qualities unaltered in any climate, and stand 
 transportation. 
 
 There are two processes that would pay well if 
 they filled all the requirements, The first is the 
 
46 Hints to Inventors 
 
 substitution of something for the India rubber used 
 in making stamps; the second, or alternative, is to 
 "vulcanize" the India rubber itself without the use 
 of steam. The resultant " vulcanized "mass must not 
 harden with cold or age, nor soften under the same 
 influences. 
 
 Among the many really necessary inventions is 
 one which will keep ordinary "soft rubber" soft 
 and good in all climates, and for at least four years. 
 Any one who has remarked how elastic ribbons 
 such as are used in men's suspenders, in elastic 
 stockings, etc., get worthless in two years, or less, 
 will see where such an invention would come into 
 play. 
 
 For the manufacture of "denatured" alcohol — 
 that is, alcohol which has been rendered absolutely 
 undrinkable, and which is in many countries un- 
 taxed — there is desired a substance that is disgust- 
 ing in taste, so as to make any beverage made from 
 the alcohol "denatured" therewith absolutely un- 
 drinkable, without being poisonous, but which would 
 not make the alcohol smell disgusting either when 
 in the liquid state or in evaporating or burning. At 
 present "pyridin" seems to have the most extended 
 application. 
 
 The manufacture of calcium carbid calls for a 
 very great expenditure of electricity. The rapid 
 development of the industry despite this disadvan- 
 tage is, however, a proof that a cheaper cost of man- 
 ufacture would bring tremendous success. 
 
Chemical 47 
 
 So-called "solid alcohol" we have already; but 
 petroleum and benzin rendered similarly available 
 for safe transportation and use have not yet appeared. 
 
 For the preservation of lumber against decay no 
 fully suitable material has been discovered. At least 
 those which would preserve the wood, once they were 
 therein, cannot be made to penetrate into the interior 
 of the pieces to be impregnated, or if they do reach 
 the inner portions they are readily washed out by the 
 action of water or even of the weather. In this par- 
 ticular the Germans have proved themselves the 
 best chemists, and the Americans have produced 
 the most effective apparatus for forcing the impreg- 
 nating-fluids into the pores of the wood. But there 
 is much left to be done in both matters. The de- 
 sired material must not discolor the wood, if this 
 latter is to be used for interior house-building pur- 
 poses; must leave it inodorous; must not increase 
 its inflammability; if possible, should render it prac- 
 tically incombustible, and should have no action on 
 nails driven into the wood, glued joints therein, or 
 paint used thereon. 
 
 A cheap process for manufacturing cyanide of 
 potassium is loudly called for. 
 
 An inexpensive manner of deodorizing some sorts 
 of petroleum — as for instance that from Texas, 
 Lima, O., Canada, and Russia — would be a great 
 boon, as it would make these oils available for use 
 in lamps, and render them less harmful to the iron 
 of boilers under which they were fired. 
 
48 Hints to Inventors 
 
 We have meat extracts of all sorts, liquid and 
 pasty; but who will prepare a good article of dried 
 or otherwise preserved milk, free from sugar, that 
 will be thoroughly soluble in water or in coffee and 
 tea ? The milk powders that are on the market are 
 not fully soluble; they curdle. The trade would 
 readily take two varieties of dried milk — with and 
 without cream — that is, dried unskimmed and dried 
 skimmed milk. Both must, however, possess all 
 the above-named qualities, and keep well in any cli- 
 mate for any length of time. The process must not 
 affect the digestibility, even in the stomachs of 
 young children. 
 
 There are on the market many preparations of 
 margarin and similar substances; what is further 
 needed is a process of making out of tallow a whole- 
 some food product. 
 
 The secret of the varnish which the violin-makers 
 in the seventeenth century used seems to have died 
 with them. That it had a great and most favorable 
 influence on the tone of the instruments on which 
 it was used, violin experts are unanimously agreed; 
 and among them there are no two opinions as to 
 the desirability of rediscovering the compound. Un- 
 fortunately, the experiments must be only synthet- 
 ical; for no one would permit the analysis of the 
 varnish on a violin having a worth of ten thousand 
 dollars — which, for example, was the price paid by 
 Colonel Partello for one of his famous instruments. 
 
 There is only one factory in the world — it is in 
 
Chemical 49 
 
 Germany — that has succeeded in producing a good 
 artificial indigo ; and to bring this on the market has 
 required the outlay of an immense capital for the 
 necessary plant to produce the materials called for. 
 The industry is one which brings in millions. 
 
 As the so-called "smokeless" gunpowder nearly 
 suffocates those in the neighborhood of the yellow 
 vapors produced, and as the half-burned particles 
 discharged from the muzzle of the gun are, to say 
 the least, highly unpleasant if they fly in one's face, 
 it would seem as though there was a good opportu- 
 nity for some capable industrial chemist to hand his 
 name down to fame by inventing a "Smithite" or 
 a " Jonesite" or some other "ite," in the neighbor- 
 hood of which those using it, or near where it is be- 
 ing used, could find comparative comfort. This 
 "powder" (if we may call that powder which comes 
 in sticks as big as a lead-pencil, or grains as large 
 as a walnut) must have high explosive force, but 
 not be explodable by shock. It must stand moist- 
 ure reasonably well, neither change with time, in- 
 jure the bore of the gun, nor dirty it very much ; and 
 in exploding must generate no poisonous gases. It 
 must burn comparatively slowly, in order not to put 
 too much strain on the breech of the gun, before the 
 shot is in motion, but must be fully exploded and 
 changed to gas by the time the missile has reached 
 the muzzle of the piece; otherwise there would be 
 not only a loss of powder, but also unpleasantness 
 for those in the neighborhood — especially on board 
 ship. 
 
50 Hintsto Inventors 
 
 This "powder" must be made of materials that 
 are to be had not only somewhere in the country for 
 which the explosive is intended, but right in the 
 neighborhood of the manufactory; and such mate- 
 rials must be capable of being rapidly converted 
 into the explosive. It would be an advantage if the 
 powder had a high specific gravity, in order to re- 
 duce freight charges and facilitate its transportation 
 by the army. 
 
 There is very much room for improvement in 
 cements for porcelain and glass, especially for such 
 as the lamp-manufacturers use to fasten glass and 
 metal together, as for instance where the glass bowl 
 of a hand-lamp is cemented into the metal cup at 
 the top of the pillar or stand. 
 
 Find a substitute for glass as a material foi tele- 
 scopic and microscopic lenses, having as great a re- 
 fractive power as the diamond — and name your 
 own price for it. 
 
 Oxygen-making and hydrogen-making are not 
 yet easy enough or cheap enough on a large scale. 
 
 The number of possible new alkaloids would pos- 
 sibly bankrupt one's arithmetic to compute. It is 
 probably feasible to produce them to order, having 
 any desired effect upon the human system. 
 
 In the manufacture of paper, such matters as 
 strengthening and toughening thin sheets without 
 making them stiff and brittle have yet to be looked 
 into. A soft, flexible parchment paper is needed. 
 
 In paper-making there is needed a chemical pro- 
 
Chemical 51 
 
 cess for making wood pulp, which will destroy the 
 fibre less than the present. 
 
 There is room for a domestic bleaching powder 
 or fluid which shall not corrode the ordinary textile 
 fabrics. 
 
 To supply some solution which will have the gen- 
 eral effect of creosote in preserving wood from rot, 
 but shall not be dissolvable out of the wood, if the 
 latter is immersed in water, is a great thing for which 
 to try. 
 
 A better material for decorated picture-frames is 
 highly desirable; that now used is too brittle and 
 soft. 
 
 Up to date there seems to be but one glaze for 
 coffee-beans to prevent their losing their aroma 
 after being roasted. That glaze is sugar, of which 
 the patentee or special exploiter of the process says 
 that he uses about three per cent. It forms on the 
 berry a coating of caramel. This has its disadvan- 
 tages: it is not proof against moisture, and persons 
 afflicted with Bright 's disease should not take even 
 so small a quantity of sugar into the system. Even 
 if it would do them no harm, they would fear that 
 it would, and so not buy the glazed coffee. Verbum 
 sap. 
 
 Sculptors and manufacturers of picture-frames 
 would like a better material than the glue-and- 
 molasses, or glue-and-glycerin, mixture which they 
 now use to make undercut casts of plaster of Paris 
 and compositions thereof. The mass now used gets 
 
52 Hints to Inventors 
 
 moldy soon, and is affected by heat and moisture, 
 so that if the molds are not used soon after making 
 they are useless. 
 
 Patent-leather manufacturers seem to be without 
 any material by which their wares can be given a 
 new bright surface when the old finish is destroyed 
 by moisture or by friction. There are plenty of 
 "creams" that are merely smears, which give a sort 
 of a polish; but they either build up a gradually 
 increasing layer of new varnish, or make a greasy 
 coating that the least rubbing destroys. Perhaps 
 it would be possible to renew the surface by a par- 
 tial dissolving of the outer layer, thus running the 
 material together, as is done in the restoration of 
 old oil-paintings the varnish of which has become 
 badly cracked. 
 
 There are few processes — perhaps only one — 
 by which glove kid can be cleaned and left soft and 
 flexible without removing the outer layer and con- 
 sequently "scuffing" away the color. The same 
 holds good of fine morocco, such as is used for la- 
 dies' shoes. These will not bear washing when they 
 get very muddy; and dry cleaning does not suffice. 
 
 For household utensils there is needed a better 
 white enamel than is at present on the market. The 
 prime requisites are that it shall be resistant to acids 
 and alkalies such as are to be found in the average 
 household, and stand fight blows without chipping. 
 For those utensils which are used for cooking pur- 
 poses, the enamel must not only be quite resistant 
 
Chemical 53 
 
 to heat, but to a certain extent able to expand and 
 contract with the varying temperature of the sheet 
 metal on which it is baked or burned. And further, 
 it must be free from lead or other poisonous ingre- 
 dient. 
 
Chapter III. 
 METALLURGICAL 
 
 Every now and then somebody claims (or some 
 one else claims for him) that he has discovered a 
 process by which to isolate aluminium at very little 
 cost. Some good starts have been made in this di- 
 rection, but we are only in the a-b-ab's of this metal- 
 lurgical industry. There may be a dozen processes, 
 each of which would pay well and all of which would 
 be as satisfactory as the ones now being worked. 
 
 Now that aluminium is so cheap there is a demand 
 for better solders for it than are known at present, 
 even to experts. 
 
 Metallurgists want a cheap processs for extracting 
 silver from very low-grade ores in paying quantities. 
 
 Hardening copper is an art which, it is said, was 
 once possessed by the ancient Egyptians. If they 
 had it they lost it completely; and when they lost it 
 they lost a very valuable art. The re-inventor of 
 the old process, or the discoverer of a new one, should 
 become famous and rich. 
 
 If you could only extract the gold from ordinary 
 brick clay, in somewhat the same manner as the 
 aluminium is now taken out of it, you might think 
 Croesus a poor man compared with you. There is 
 enough gold in an ordinary Philadelphia brick to 
 make a piece of gold-leaf two inches square. 
 
 [54] 
 
Metallurgical 55 
 
 A good way of recovering the tin from scrap- 
 tinned iron should pay. 
 
 The whole art of making castings under pressure 
 needs to be learned. It is but in its infancy. There 
 is required a casting-machine which will do in steel, 
 iron, and brass what the type-casting machine does 
 in type metal. 
 
 Direct processes for making iron and steel from 
 the ores should engage the attention of practical 
 metallurgists. There would be but little use for an 
 outsider to work on this line; there are too many 
 things about it which must be learned by long-time 
 observation and experience. 
 
 There is only about one firm in America that 
 can make what is known as Russia iron; and the 
 recipe for doing it is not posted upon its outer walls. 
 
 In steel-making there are ever so many possible 
 compounds of iron with other elements, which would 
 have value for special purposes if they were exper- 
 imented with. Other steels than carbon, silicon, 
 and chromium compounds should be worked out 
 and experimented with. 
 
 [Since this hint was given, in 1892, the entire 
 machine-building industry has been revolutionized 
 by the new steels then pointed out, and which ap- 
 peared in 1900. The new vanadium, tungsten (or 
 wolfram), and molybdenum tool steels cut five times 
 as fast as the old-fashioned carbon steels, and do 
 their best work at high temperatures which would 
 
56 Hints to Inventors 
 
 ruin their predecessors. There is, however, room 
 for more experiments and more progress.] 
 
 In the matter of hardening these new steels, the 
 consumer is at a disadvantage, for no two of them 
 call for the same treatment, and many of their man- 
 ufacturers prefer to harden all tools made from them, 
 themselves. Special hardening appliances therefor 
 are commencing to appear; some of them employ 
 electricity to heat the material; and some, com- 
 pressed air to cool it. 
 
 Up to date there is a shortage in the number of 
 useful additions to iron; namely, one which will 
 make pig iron at once malleable. At present there 
 is no intermediate doughy state which precedes the 
 melted condition. If there were a material which 
 could be added at the time of melting to produce 
 this intermediate pasty condition, and thus permit 
 pressing or forging the doughy metal in molds, it 
 would be a most welcome addition to the materials 
 used in siderial metallurgy. 
 
 Regenerative gas stoves made a complete change 
 in the iron and steel industry, but are as yet far 
 from perfect. The author finds the masonry too 
 dear. If nothing else can be done to cheapen their 
 construction, then it might do to invent a process by 
 which large blocks of fire-brick material could be 
 manufactured, preferably with perforations therein 
 which would enable them to be built in so that 
 each could take the place of several smaller bricks 
 with interstitial passages. 
 
Chapter IV. 
 MINING* 
 
 There is needed a Davy lamp which is of simple 
 construction, cannot be opened by the miner or by 
 any appliance that is to be found except in the 
 lamp-station outside of the mine, but the flame of 
 which can be adjusted or extinguished by the miner. 
 
 No one has succeeded in producing a machine 
 or process which will separate graphite from the 
 mica and quartz with which that mineral is so often 
 associated. These have the same specific gravity 
 as graphite, and, like it, are unaffected by acids, 
 alkalies, or high temperatures; and the most val- 
 uable form of graphite is flaky, which makes a still 
 stronger point of resemblance between it and mica. 
 Rock-drills operated by compressed air are sub- 
 ject to a particularly annoying peculiarity: the ex- 
 pansion of the exhausted air causes the formation of 
 snow at the exhaust outlet, and the combination of 
 this with the oil used in the cylinder is very apt to 
 clog the exhaust and interfere with the working of 
 the machine. 
 
 A prize is offered for a strong and reliable safety 
 appliance to hold a mine-car in case the rope breaks. 
 
 *See also the chapter " Inventions for which Prizes Are 
 Offered." 
 
 [57] 
 
58 Hints to Inventors 
 
 The damage caused by a wagon which gathers 
 speed as it runs down the slope is often very great 
 — and of course we must take account of the dan- 
 ger to human life and limb. 
 
 Some one should get up a machine for sorting 
 the slate out of coal — a " dry" process preferred. 
 
 A good coal-cutting machine would bring buy- 
 ers from all over this country, to say nothing of the 
 world at large. Coal is too dear. It should be got 
 out of the mines more cheaply, so that from one end 
 of our broad land to the other no poor person need 
 either freeze or shiver. 
 
 If some one would go out in the oil region with a 
 good "grapple" for well-boring tools, he would have 
 a mob of purchasers about him in short order. 
 
Chapter V. 
 RAILWAYS AND TRAMWAYS* 
 
 There is a chance for practical inventors to 
 change the whole idea of railway -train braking. The 
 brake should be applied to the rail, and not to the 
 wheels of the train. Brakes applied to the wheels 
 simply permit the train to skid, and cause flat places 
 on the wheels. Brakes applied to the rails would 
 ease the momentum of the train in friction between 
 it and something not within itself. 
 
 [When the author first advanced this idea, about 
 1872, he was very liberally derided by those who 
 "knew better." He took comfort in the endorse- 
 ment of America's foremost civil engineer, the late 
 John C. Trautwine, of early Panama Railway re- 
 nown, and bided his time. In 1892 he again gave vent 
 to his opinion on the subject, in the first edition of this 
 work. Since then, one of the most prominent man- 
 ufactories in the world has adopted it for electric 
 railways.] 
 
 There is need of a device by which a train can 
 be stopped at any point in its run from any station 
 
 *See also the chapter "Inventions for which Prizes Are 
 Offered." 
 
 [59] 
 
60 Hints to Inventors 
 
 of a line. This is needed not only in the case of 
 "wild" engines which have escaped control, but 
 for trains which have gone past a signal, or have 
 not heeded it, or are not within signaling-range. 
 
 [This call for a device by which trains could be 
 stopped in an emergency, without the concurrence 
 of the trainmen, was almost at once answered by a 
 Hollander, who, however, entrusted his patent ap- 
 plication to a "bureau" run by a man who had not 
 the requisite familiarity with his own business to 
 make the application in proper form and time, so in 
 this instance his work was unfortunately "love's 
 labor lost."] 
 
 The problem of car-heating is not yet as well 
 solved as it needs to be and as it will be some time in 
 the future, when the deadly car-stove is definitely 
 abolished from off the face of the entire earth. One 
 reason for the obstinate retention of the car-stove is 
 that the "powers that be" are waiting for the best 
 thing which can be produced to supplant it. The 
 field is still open for intelligent competition of brains. 
 
 A station-indicator which will show what will be 
 the next stopping-place, and will skip those at which 
 the train does not stop, is loudly called for by the 
 traveling public; and railroad officials and employ- 
 ees would be prejudiced in its favor. 
 
 Did any one — expert or non-expert — ever see 
 a perfect rail-joint for steam roads or electric tram- 
 
Railways and Tramways 61 
 
 ways ? When we reflect that the joint is the weak- 
 est part of the road, and that by reason of its weak- 
 ness the entire road is just as weak as that weakest 
 part, the importance of the matter will appear. 
 
 As our timber supply is getting less and less, there 
 is more and more need for a good iron or steel rail- 
 way tie. 
 
 There is still room for another snow-plow — one 
 which will cut its way bodily through deep snow, and 
 throw the material removed out of the way, where 
 it will not cover the adjoining track. It must be able 
 to throw the material from the right-hand track clear 
 over the left-hand one, and vice versa, and deposit 
 it so that it will not come down again. 
 
 Locomotives that do not burn coke or oil are apt 
 to throw sparks, and the spark-catcher has been a 
 frequent subject for patents. But whether a de- 
 flector or a screen, it has not shown itself to be per- 
 fect, and the railway companies still pay large sums 
 for burned property, and probably evade the pay- 
 ment of still larger amounts. The nuisance to pas- 
 sengers is, of course, unfortunately only a side issue. 
 The companies would not mind being able incident- 
 ally to prevent the discomfort to passengers ; but this 
 burning of crops along the route, and setting fire to 
 cotton on gondola cars, must be stopped, if any in- 
 ventor can be found who can stop it. Of course, the 
 proposed spark-arrester must not make back pres- 
 sure on the engine, nor reduce the draft through 
 the grate. 
 
62 Hints to Inventors 
 
 It would be very convenient if the train hands 
 could light and extinguish the car lights from the 
 car platform, instead of having to run along the 
 roof to do it. 
 
 Hot-box signals have not yet been generally in- 
 troduced, because those which have been offered 
 have not been satisfactory. There was one which 
 consisted of a piece of red paper that turned brown 
 if the box to which it was affixed ran hot; but 
 what would be better would be one to give the 
 engine-runner, or the engineer, or the conductor, 
 as the case might be, an audible signal at his post. 
 Until this is invented we might make use of the vis- 
 ual signal for all journals or boxes which are not 
 within hand reach. For fast through trains the 
 colored-spot device has of course no use; in such 
 cases there must be a bell rung in some part of the 
 train where the proper employee can hear it. The 
 device must be sold cheaply, and not be affected 
 by bad weather nor by changes of temperature. 
 
 It is remarkable that so many engineers and 
 others who have the inventive talent, and also the 
 inventive habit, have seen, so many thousands of 
 times, the driver or the conductor of a tram car get 
 out and throw a switch-point. This should be done 
 from the car platform. There is one method by 
 which the horse of a one-horse car can be made to 
 step on one side or another of a plate lying between 
 the rails, so as to throw the switch to right or to left ; 
 but nowadays one-horse cars are getting scarce, and 
 
Railways and Tramways 63 
 
 there should be a device by which the switch can be 
 thrown while the car is moving, and from such a 
 distance that no matter how great its speed, the 
 switch shall be open or shut, or thrown right or 
 left, as desired, when the car gets to it. 
 
 The terrible accidents of 1900 and 1901 in Ger- 
 many, which resulted in the passengers of a derailed 
 train being roasted alive by the gas escaping from 
 the reservoirs of a wrecked car, should have been 
 incentive enough to inventors to have resulted in 
 the production of a safety system by which a repeti- 
 tion of this horror could not take place; but as yet 
 gas-lighted cars are in the same dangerous position. 
 Putting the reservoir on the car roof does not help 
 matters, as cars are so often overturned in derailing. 
 
 The author will not pretend that the theoretical 
 car-coupler has been invented, still less brought into 
 universal use. But it is a fact that the demand for a 
 good coupler to take the place of the many imper- 
 fect ones formerly in use brought out so many hun- 
 dreds of models, and caused the lives of the railway 
 officials to be such a burden, that at present the 
 prospect of a new coupling being adopted or even 
 tested is too slight for it to be worth the while of any 
 inventor to put time and money in working up this 
 line. 
 
 The length of the wire, rope, or chain used to 
 throw switches or signals at a distance is so apt to 
 be affected by changes of weather, or increased by 
 stretching in use, that it is better to perform such 
 
64 Hints to Inventors 
 
 operations electrically. There are in use two quite 
 good systems for doing this, but they are not so 
 nearly perfect as to prevent inventors producing 
 something entirely different and just as good for 
 less money, or simplifying and improving those now 
 in use. 
 
 There is still the want — let the author say the 
 positive necessity — of a device by which the engine- 
 runner may receive in his cab an audible signal if 
 there is another train, or part of a train, within a 
 specified distance of his own, no matter whether be- 
 fore or behind him, nor in which direction it is run- 
 ning, if at all. 
 
 A platform weighing-machine which will record 
 the weight of each car of train passed over it ought 
 to pay. 
 
 Car-starters for street-railway lines have not been 
 given enough attention. There must be something 
 which will store up enough power when the car is in 
 motion to start it easily when fully loaded, after it 
 has been brought to rest. If it can be still further 
 developed so as to store up while on down grades a 
 certain amount of power, and give it out again on 
 the up grades in aid of the horses, there will be money 
 in it. 
 
 The cable-railway men have not yet found a per- 
 fect grip. The ones that they have are defective, and 
 they know it. Verbum sap, 
 
Chapter VI. 
 MARINE* 
 
 The perfect hull model is not yet. 
 
 Some one should invent a fire-proof and unde- 
 cayable wood with which to cover the iron and steel 
 work on board ship. 
 
 There is still room for the invention of a cheap 
 cellulose-like material for filling the space between 
 the hulls in a double-hulled vessel, so that if a shot 
 or any other cause make a hole or a rent, this mate- 
 rial will at once swell with the water and prevent the 
 filling of the compartment back of the injury. This 
 result has been attained to some extent with cocoa- 
 nut fibers, Indian corn pith, etc. ; but the demand is 
 not yet covered by the supply. The material must 
 be light, very absorptive of water, highly compressi- 
 ble, and if possible fire-proof and non-decayable. 
 
 The perfect screw propeller is not yet in metal, 
 and, probably, is not yet on paper. Here is a won- 
 derful chance for those who are "up" in the mys- 
 teries of propulsion to produce something which will 
 benefit mankind and also make the inventor rich, if 
 he handles his invention properly. 
 
 Hydraulic ballast for large ocean steamers is not 
 
 *See also the chapter "Inventions for which Prizes Are 
 Offered." 
 
 [65] 
 
66 Hints to Inventors 
 
 yet as perfectly applied as is desirable. Here is 
 your chance. 
 
 Can you make a better feathering paddle-wheel 
 than those which are in use ? If so, do not hide your 
 light under a bushel. 
 
 Jet propulsion of vessels is being tried, but there 
 is plenty of room at the top in this line, and there is 
 cash at the top for those who get there. 
 
 Something better than the present naphtha 
 launches would be snapped up greedily by those 
 who love the water and have no knowledge of 
 engine-running. 
 
 The great storm at Samoa should have convinced 
 any one that there is need of a better anchor than 
 those which failed to hold the ill-fated vessels in that 
 notable harbor. 
 
 There is also need of a better boat-disengaging 
 hook than is used in our (or any other) navy. 
 
 The life-boat offers an excellent opportunity for 
 invention in a line which should be at once profit- 
 able and humanitarian. There is no boat which will 
 stand a heavy sea without capsizing or being stove 
 in. 
 
 Any one who looks at the cumbersome methods 
 employed in dredging out our harbors (and even 
 they are far in advance of those used in other coun- 
 tries) will admit on sight that there is need of better. 
 
 The correct way to make a screw propeller is by 
 some other method than those which have been 
 tried up to date, 
 
Marine 67 
 
 That a gyroscope can prevent the rolling of a 
 ship is well known; as yet, however, the principle 
 has not been practically developed; and here is an 
 opportunity for some inventor who understands not 
 only the principle of the gyroscope, but something 
 of practical ship and marine engine building, to work 
 out an application of the gyroscope to ocean steam- 
 ers, especially those for passenger traffic. 
 
 [Since writing this, considerable progress in this 
 connection has been made.] 
 
 Strange as it may seem, all attempts to replace 
 wooden masts and yards with hollow ones of iron 
 or steel have proved unsatisfactory. Like the steel 
 wire-rope rigging, they seem to lack the requisite elas- 
 ticity. Be that as it may, there is a field open ; some 
 day the reason for the failure will be discovered, 
 and when that is done the invention of the remedy 
 need not follow at any great distance. The solution 
 may he found in a manner of making seamless steel 
 tubes of the required length, with walls of thickness 
 gradually diminishing towards the tip. 
 
 Iron ship builders do not seem to be thoroughly 
 satisfied with the riveting-machines which they have, 
 whether they be driven by compressed air, by steam, 
 or by water. They are as a rule too unhandy. 
 
 It would be very desirable to replace the hemp 
 ropes (as a landsman would call them, although 
 from the nautical standpoint there is but one " rope" 
 
68 Hints to Inventors 
 
 on board, the "rope's end") by wire; but the diffi- 
 culty lies in the lack of elasticity of the latter. Where 
 any great strain comes on the masts and shrouds, if 
 these latter are of wire rope and do not break under 
 the strain, they are apt to rip something loose. Ca- 
 bles and sheets (the word here used in the sailor's 
 sense) which would be as strong as steel and as elas- 
 tic as hemp would be "a consummation devoutly 
 to be wished." 
 
 There is need of a varnish or similar compound 
 for the hulls of iron vessels, and still more so for 
 those of steel, which would be smooth and resistant 
 to wear, and prevent, or at least not encourage, the 
 formation of barnacles and other growths which so 
 seriously impede the progress of the vessel. The 
 material must if possible be a quick drier, as dock- 
 ing-charges are high, and war-vessels cannot always 
 spare the time to be laid out of commission a long 
 while to be scraped and painted. It was said long 
 ago that the Japanese, from whom we have to learn 
 so many things, had such a compound, the only ob- 
 jection being the long time required to dry. Then, 
 however, time was less of an object to the Japanese 
 than now. 
 
 By reason of the increasing weight of ships' hulls, 
 there is an increasing necessity for improved launch- 
 ing-ways. 
 
Chapter VII. 
 MILITARY 
 
 Smokeless powder now used for cannon has 
 among other bad qualities that it leaves the bore of 
 the gun covered with a muddy deposit which mars 
 the accuracy of the aim and increases the difficulty 
 of cleaning — thereby, of course, lessening the speed 
 of loading and firing. Therefore, in working along 
 this line, perfect combustion of all the ingredients 
 is to be aimed at. The nearer it is attained, if not 
 at the sacrifice of some other good quality, the better. 
 (See also the chapter " Chemical.") 
 
 Safety -devices for rifles and revolvers, which pre- 
 vent firing unless the finger is on the trigger and the 
 cock or bolt raised or withdrawn, are greatly to be 
 desired. There is such a device, and a very good 
 one, but it is controlled by a single firm, so that a 
 competing device, if just as good, at the same price, 
 would go well. 
 
 To design a limber for field artillery which would 
 weigh about one third less than the present ones, 
 so as to make up for the increase in weight of the 
 cannon, due to the recoil devices and the steel shield 
 now usual, is a problem which should be attacked 
 only by those familiar with the demands of the serv- 
 ice. 
 
 [69] 
 
70 Hints to Inventors 
 
 Those who take an interest in matters warlike 
 will find in the breech-loading cannon opportunity 
 for them to try their mettle and their metal, too. 
 
 The task of producing a recoil device for field 
 artillery, which would be reliable under all circum- 
 stances, and be more simple, yet stronger, than those 
 now in use, has been confided to several experts; 
 but their knowledge of what is needed seems to be 
 greater than their ability to produce the desired 
 arrangement and construction. 
 
 Some one will come along and throw dynamite 
 shells out of an ordinary cannon with a high explo- 
 sive to propel it; and then he will most likely be 
 both famous and rich. 
 
 The air-gun as a weapon in regular warfare has 
 not yet been given the attention which the possibil- 
 ities of the case would seem to call for. Being smoke- 
 less and practically silent, it should be a very useful 
 weapon. Zalinsky has shown us long ago what it 
 can do in the way of throwing dynamite. 
 
 For camp purposes the officers should have a 
 good portable folding writing-table, which when 
 opened out for service should be absolutely rigid, 
 and stout enough to bear considerable weight. It 
 goes without saying that such a table should weigh 
 but little, and be so simple as to be easily and 
 quickly put together by an ordinary servant, or by an 
 orderly. 
 
 The folding beds which are delivered for army 
 use might very well be better, from the point of view 
 
Military 71 
 
 of stiffness, strength, and preservation of their orig- 
 inal lines. Further, some of them, once bent in 
 transportation, are hardly to be opened out, much 
 less set up. If a bridge-builder were to combine 
 with a sailor in designing such a bed, it would be 
 apt to fill the bill, if the cost of production could be 
 kept down. 
 
 The requisites of a good army tent are that it 
 shall be light, compact, rain-tight and wind-tight, 
 easily put up and taken down, not readily upset by 
 a stray mule getting in the ropes, and durable un- 
 der extremes of cold and heat; that is, it must not 
 get stiff and hard in cold weather, nor stick in warm. 
 And any common soldier must be able to put it up, 
 take it down, and fold it up, almost in the dark. If 
 possible, it should be fire-proof; and most assuredly 
 it should be proof against mildew if folded up wet, 
 as it is sure to be. 
 
 Navigable balloons and aeroplanes for military 
 and other purposes are not beyond the reach of hu- 
 man capabilities. Some very successful attempts 
 have been made by Santos-Dumont, the Renaults, 
 the Wright brothers, and others. There are details 
 which need to be worked at. Whoever gets them 
 down to a practical shape need have but little diffi- 
 culty in sailing the air, and in going where he pleases. 
 
Chapter VIII. 
 MACHINE CONSTRUCTION* 
 
 In the matter of ball bearings, cone bearings, 
 and roller bearings there is field enough for a dozen 
 more inventors than those who are already making 
 money in this line. There is still room for anti- 
 friction bearings that can be manufactured by the 
 hundred or the thousand, according to their size 
 and character, and used by machine-manufactur- 
 ers just as they would use any other standard sup- 
 ply, as lubricators or keys — simply put in place. 
 If such bearings were made on a scale large enough, 
 and backed by a company with capital, ability, and 
 experience, machine-builders would redesign their 
 drawings most willingly, so that they could just slide 
 into place the style of bearing best suited to the pres- 
 sure and speed, or which might be so considered by 
 customers. 
 
 Apropos of ball and roller bearings, I should say 
 that provision should be made therein for possible 
 expansion in length of the shaft by heat; because 
 even with anti-friction bearings accidents do happen, 
 and expansion does take place. 
 
 Screw machines intended for the average shop, 
 
 *See also the chapter "Inventions for which Prizes Are 
 Offered." 
 
 [72] 
 
Machine Construction 73 
 
 and not for the manufacturer of screws alone, would 
 go well if it were not necessary to adjust too many 
 cams or stops every time the pitch or the length was 
 to be changed. 
 
 The perfect machine for grinding railway-car 
 wheels and locomotive wheels does not stand in 
 any shop in either Europe or America. There are 
 good ones, but too few of them have cut loose from 
 old and preconceived ideas. Newton of Philadel- 
 phia was one of the few machine-tool builders who 
 had more confidence in the judgment of the cus- 
 tomer, as to what was needed, than in his own on 
 the subject in question. His development of the 
 cold metal saw for railway-shops is a good example 
 of the value of finding out, before commencing to 
 design a machine, what the users of such machines 
 found to be faults in these latter, and what would 
 be desirable in a new type. The wheel-grinding 
 machine should work the wheels true to diameter 
 and profile, and correct its own faults, as is the case 
 in the calender-roll grinding-machine invented by 
 the late J. Morton Poole. The machine should 
 grind both wheels at once, and alike, no matter how 
 much more one was flatted or otherwise worn than 
 the other. It would also be advantageous to grind 
 the journals at the same time — and would it be 
 going too far to ask that the appliance for grinding 
 the pins of locomotive-drivers should take up the 
 work after the journals and tires were true, and do 
 the pins also, without changing the setting of the 
 
74 Hints to Inventors 
 
 wheels? Such a machine calls, naturally, for two 
 kinds of centering : on the conical centers, to permit 
 grinding the journals true, and then doing the tires 
 while the pair turned on its own journals. The 
 crank-pins should be turned while the set is mounted 
 on the journals. 
 
 No cheap process for making twist-drills with 
 oil-grooves is as yet at the disposal of manufactur- 
 ers of such drills. The improvements in steel call 
 for better drills; but there are limits to the prices 
 which will be paid for drills with oil-grooves. 
 
 Inventors are very fertile-minded, but the need 
 of a good flux for brazing cast iron remains un- 
 noticed or unconquered. 
 
 Of the making of die-stocks for screw cutting or 
 threading there is no end; but there is yet room. 
 
 The increasing use of water under pressure in 
 machine-shops should encourage inventors to pro- 
 duce hydraulic cranes and jacks — the latter not 
 merely for lifting weights, but for pressing in and 
 out bushings, plugs, shafts, mandrels, etc. Bol- 
 linckx of Brussels presses in plugs where he finds a 
 fault in a cylinder casting; the work is cheaper and 
 better than threading both the hole and the plug, 
 and screwing the latter into the former. This is 
 only one instance of dozens about a shop where hy- 
 draulic pressing could be used to advantage. 
 
 The micrometers which are in the market have too 
 little range; it would be well to get up some which, 
 while they would have the fine adjustability of the 
 
Machine Construction 75 
 
 present ones, would be able to take in a greater 
 range of lengths or diameters. 
 
 The use of "boart" or black diamonds for tru- 
 ing off emery-wheels is much handicapped by the 
 difficulty of getting them firmly set in metal. Galvan- 
 oplasty has done much to help out in this respect, 
 but this requires a special electro-depositing plant 
 and a skilled man to run it. A good all-metal set- 
 ting, requiring no electric appliances, would be well 
 received. 
 
 A prize has been offered for a device which 
 would prevent the running-down of the drum of a 
 crane or derrick when the load was on ; as accidents 
 often happen not only by reason of the falling load, 
 but by the rapidly rotating crank. The ratchet-and- 
 pawl device is insufficient, 
 
Chapter IX. 
 MACHINE TOOLS 
 
 The advent of the new fast-cutting steels has 
 rendered or will render necessary the remodeling 
 of almost every machine-tool now in use, and the 
 design of many more. It is not merely that the ma- 
 chine-tools built before 1900 have not the speed 
 and the stiffness to be used successfully with tools 
 of the new steels; the entire field of machine-tool 
 design and of metal-working must be gone over 
 again. The "hog cuts" that the new steels can take 
 in roughing will lessen the necessity of such exact 
 forging as has been necessary to avoid turning off 
 much metal; and the failure of the same tools to 
 finish as well as their predecessors will make ma- 
 chinists have recourse to the emery-wheel and its 
 congeners twice as often as before. 
 
 Outside of this, new problems are presented and 
 old ones posed more often than before. 
 
 The lathe, for example, is called upon, even in 
 non-metric countries, to cut metric threads; and 
 still the old denominations must be kept. There 
 must then be lathes which without taking them to 
 pieces and putting in other lead screws can change 
 from inch to centimeter pitches by the throw of a 
 lever, just as the present ones of late design can vary 
 the pitch by sliding a button in a groove. 
 
 [76] 
 
Machine Tools 77 
 
 There is also call for increased facility for grind- 
 ing on the lathe pieces already roughed thereon; 
 chucking being inadvisable, as giving rise to inac- 
 curacy, and being expensive. It may be better to 
 finish by grinding on the same lathe that does the 
 roughing. 
 
 Then lathes with drive from both ends are getting 
 into favor, to enable a thread to be cut on both ends 
 of a piece that is plain cylindrical in the middle, or 
 to turn off a very long piece without having to turn 
 it end for end. 
 
 Better taper-turning facilities are also called for. 
 
 The compound rest is very convenient, and we 
 all wonder how our grandfathers did without it. 
 Our grandchildren will, however, wonder how we 
 ever dispensed with attachments for turning and 
 boring spherically. 
 
 The planer has been improved by side heads and 
 milling-attachments; but arrangements for convex 
 and concave planing belong to the planer, and should 
 be furnished therewith. 
 
 The planer of the future should have, to supple- 
 ment increased speed and strength for the use of 
 the new rapid steels, a grinding-attachment by which 
 the roughed-out pieces can be finished without re- 
 chucking. 
 
 Of the radial drill of the near future the buyer 
 will demand that it shall be able to drill two paral- 
 lel holes that lie in the same vertical plane as the 
 arm. At present, as soon as the machine gets a lit- 
 
78 Hints to Inventors 
 
 tie old, and if the holes to be bored are up to the 
 full capacity of the machine, the one bored with 
 the drill at the end of the arm will be apt to be in- 
 clined from the vertical, because the arm tips up. 
 (Here it is the holes that are radial with respect to 
 each other!) 
 
 The ordinary drill-press (so called because it is 
 not a press) should be given an attachment by which 
 it could bore radial holes in a cylindrical work-piece 
 at any desired angle from one another all around the 
 whole circumference. Such work comes up often, 
 as for instance on the cores of slab milling-cutters 
 with inserted teeth, 
 
Chapter X. 
 
 RECORDING AND VENDING 
 APPARATUS, Etc. 
 
 The cash register in its many forms is a wonder- 
 ful piece of mechanism; but it does not test and 
 throw out false coins, as does the apparatus for sell- 
 ing postage-stamps, etc. 
 
 While there are cash registers for almost every 
 possible set of conditions likely to be found in large 
 establishments, small shops have received little at- 
 tention from cash-register inventors; and there are 
 more small shops than large ones. A small shop 
 with one or two salesmen can seldom afford to buy 
 an expensive register. 
 
 One can buy from automatic vending-apparatus 
 post-cards, cigars, and packages containing a very 
 small amount of chocolate done up in a prodigious 
 amount of pasteboard ; but when it comes to devices 
 for selling a quart of milk, a pint of beer, or a gal- 
 lon of petroleum, the machines are not on view. Such 
 a machine need be but a development of those used 
 in restaurants for delivering coffee, or liqueur, in 
 measured quantities. 
 
 Cheap letter-scales, which instead of giving the 
 exact weight (which interests no one but the employ- 
 ees of the registered-letter department) would give 
 
 [79] 
 
80 Hints to Inventors 
 
 only the number of "rates," — that is, would indi- 
 cate the next highest step in the scale of payment 
 — would sell like hot cakes, There are such scales, 
 and they are very well made; but they are too ex- 
 pensive. Our post-offices use some of them; Eu- 
 ropean offices do not; and this latter trade alone 
 would make a good income for the manufacturer. 
 
 A further, although more difficult, step would be 
 towards the production of an automatic letter-reg- 
 istering apparatus, so that one could drop a letter 
 into one slot, and the necessary fee into another, and 
 get a numbered and dated receipt corresponding 
 to the number and date imprinted by the apparatus 
 at the same time on the letter. At first, it would be 
 necessary only to take in letters of the ordinary min- 
 imum weight charged for. Perhaps a later refine- 
 ment called for would be to record the weight on 
 the letter and the receipt; and if the letter were of 
 a greater weight than that paid for, to return both 
 the letter and the money. More difficult tasks are 
 performed every day by automatic apparatus. 
 
 There are plenty of devices for registering the 
 time of coming and leaving of employees in estab- 
 lishments having large numbers of workmen, etc.; 
 but such devices are as a rule too complicated and 
 expensive; and some of them, while mechanically 
 nearly perfect, are based on a system which permits 
 error and fraud. The apparatus must be infallible, 
 and shut out fraud and suspicion on the part of 
 either the employer or the employee. 
 
Recording and Vending Apparatus 81 
 
 Numerous experiments have been made with 
 automatic machines for the sale of daily newspapers. 
 The difficulty has been that the average daily paper 
 seldom has a fixed number of pages, and it is not 
 in the nature of things that publishers would refuse 
 a few hundred columns of advertisements for the 
 Sunday edition just in order to keep it to the same 
 size and weight as the Monday issue. 
 
 One of the chief nuisances in drug-stores is the 
 constant call for the directory. Just when the at- 
 tendant is busy with a customer, or perhaps putting 
 up a prescription, he must either stop and get out 
 the directory or offend the caller. If the book is 
 left at the disposal of every one it soon gets de- 
 stroyed. If there were automatic machines which 
 on a certain coin being dropped into a slot therein 
 would release the directory, druggists would very 
 gladly put them in, because they would be a source 
 of income. 
 
 Nearly all the calculating-machines which are at 
 present on the market fail to meet the popular de- 
 mands. As a rule they are expensive, heavy, com- 
 plicated, and easily put out of order — or else they 
 are mere playthings that could not be used in any 
 office for making regular business calculations all 
 day long, week in and week out. As a general thing, 
 also, they are merely adding-machines, that per- 
 form multiplication and division by an extended se- 
 ries of additions or subtractions. In order to pre- 
 vent false reading of the results, it would be desirable 
 
Hints to Inventors 
 
 to have these latter printed by the machine on a strip 
 of paper. And it would be better yet also to have 
 printed all the items which go to make up the result, 
 so that errors in reading from the originals could 
 be detected by comparison therewith. 
 
Chapter XI. 
 MISCELLANEOUS MACHINES 
 
 Shortly after the writer called for a machine 
 which would make ships' chains in continuous 
 lengths, one was produced which seems to fill the 
 bill most perfectly as far as it goes; but the links 
 thus made have no cross-strut, which is very desir- 
 able to prevent the chain from kinking. The strut 
 adds but little if anything to the tensile strength of 
 a properly made chain, but kinking must be pre- 
 vented, especially on anchor-chains and those used 
 for general hoisting. 
 
 Some time ago the writer was called on to build 
 a machine which would bundle slats and narrow 
 slabs of wood about four feet long, of various widths 
 and thicknesses, and usually tapering in both width 
 and thickness. The object was to make bundles 
 which could be fired in a steamboat boiler as though 
 they were logs of wood. The device which he made 
 was crude and cheap, being built out of what ma- 
 terial there was at hand in a small logging-town. 
 There is room for some one to take up the matter 
 and carry it out to perfection, thus providing saw- 
 mills with a market for their slabs. 
 
 A machine for bundling ordinary kindling-wood 
 would pay still better. 
 
 [83] 
 
84 Hints to Inventors 
 
 A better box-nailing machine than is now on the 
 market would be a good thing to get up, particu- 
 larly if it could work on boxes of all sizes without 
 much or any special adjustment. 
 
 Brush-manufacturers call for a light and durable 
 machine for boring the backs of several brushes at 
 a time. If another machine were to be had, by which 
 the holes of the larger brush-backs could be filled 
 with the bristles, it would be welcomed gladly. 
 
 Of wood-working machinery there is endless va- 
 riety; but stone-working machines are scarce, and 
 usually, to quote our Gallic cousins, " of a simplicity. " 
 It is not to be expected that the same machine would 
 satisfactorily work sandstone, marble, and granite; 
 but it is not too much to hope to be able to get a 
 machine to dress granite at a reasonable speed 
 without plucking out flakes from its surface, or 
 stunning it so that it would not take a polish if 
 rubbed for a week. After the machine for working 
 plane surfaces is delivered, and proved worth buy- 
 ing, users will call for one for working out simple 
 moldings. It goes without saying that the tool used 
 on the machine must be of a material, character, 
 and manner of application that will not render sharp- 
 ening necessary every ten minutes, even when the 
 machine is working at top speed. 
 
 Bones are difficult to crush, and still more diffi- 
 cult to grind. Nearly all the bone-mills on the mar- 
 ket are too lightly built, and require too much power 
 to drive them, by reason of their not handling the 
 
Miscellaneous Machines 85 
 
 material in the right way. Every material requires 
 a special kind of blow or friction to disintegrate it 
 advantageously. 
 
 Besides the need of a machine by which to free 
 bones from the adhering meat, there is the want of 
 one to clean the intestines used in sausage-casings. 
 To do this by machinery has heretofore been con- 
 sidered almost impossible, as the machine that re- 
 moves all unnecessary membrane from the skin is 
 apt to shave this too thin in places, or to cut it 
 through. Either of these occurrences is fatal to the 
 worth of the intestine as sausage-casing. 
 
 If one visits the great sausage factories of Braun- 
 schweig or Wolfenbiittel one will see meat-chopping 
 machines that hack with a rocking motion; but 
 every machine is tended by a man or a boy, who 
 carefully turns the material after each passage of the 
 rocking knife. Machines which do their own turning 
 do not seem to have appeared at the headquarters 
 of the German sausage industry. 
 
 Basket-weaving remains an art which is but little 
 beyond where it was in the days of the Pharaohs. 
 Even a blind man, properly instructed, turns out 
 the same class of work as he who is blessed with 
 sight. The basket- weaving machine is not yet vis- 
 ible. Your fault ? 
 
 The machines now in use for perforating postage- 
 stamp sheets are too dear, and the machine, dies, 
 and perforated plates wear out too fast. There would 
 not be many sold, but a better class of machine would 
 sell promptly and bring a good price. 
 
86 Hints to Inventors 
 
 The manufacture of wax matches or "vestas" 
 has not kept pace with that of the ordinary wooden 
 ones. There is a call for machines which shall make 
 them by the mile and cut them off, besides putting 
 on the heads and laying them out to dry; all, of 
 course, without causing friction which would start 
 fire in the line. [The word "wax" here includes all 
 the cheap compositions of paraffin, spermaceti, 
 ozokerite, etc., which are at present used for can- 
 dles and tapers.] 
 
 Manufacturers of envelopes inform the author 
 that the machines in general use for folding, gum- 
 ming, and drying envelopes are not suited for ma- 
 king certain shapes with extra long tongues. The 
 manufacture of these by hand is too expensive and 
 takes too much time to enable them to be put upon 
 the market at any but prohibitive prices. The au- 
 thor knows of a case where the inventor of a pa- 
 tented envelope was prevented by the above-named 
 difficulty from developing his patent. 
 
 There is needed a cheap method of manufactur- 
 ing pasteboard tubes for mailing drawings, engra- 
 vings, etc. The tubes should preferably have one 
 end permanently closed and the other fitted with a 
 cap, easy to be removed but difficult to lose. 
 
 There is no device for filling and closing coin- 
 rolls. One for each size would be good; an adjust- 
 able one, which would pack any size for which it 
 was adjusted, would be better. Banks and post- 
 offices, as well as department-stores, would buy 
 them. 
 
Chapter XII. 
 FOUNDRY PRACTICE 
 
 Foundries suffer from the lack of a good process 
 of cleaning castings without the use of acids which 
 weaken them. The sand-blast does excellent work 
 on many kinds of pieces, but on some it is too severe, 
 and on others involves too much labor. 
 
 Small foundries could use to advantage a small 
 molding-machine; and as there are more small 
 foundries than large ones, this want should not go 
 unheeded. 
 
 The sand mold is better understood nowadays 
 than formerly, for the reason that founders are com- 
 mencing to distinguish between sand and sand, and 
 by means of blends of various sorts, as well as by 
 the addition of various compounds of glue, water- 
 glass, etc., they are getting molds to suit the differ- 
 ent kinds of patterns, cores, and iron. But there is 
 much small work where an artificial material would 
 do better than any natural sand or any blend of va- 
 rious sorts thereof. The desired material must be 
 resistant enough to withstand the pressure of a good 
 head of melted iron, and the expansion at the mo- 
 ment of solidification; must at the same time be 
 porous enough to permit the passage of the gases 
 generated in pouring, especially where there are no 
 
 [87] 
 
88 Hints to Inventors 
 
 cores to help vent ; and must either give smooth sur- 
 faces without the necessity of facing, or at least per- 
 mit of facing without danger of breaking down on 
 the sharp edges. 
 
 Bronze-founders call for a molding-material 
 which will not form a crust on the castings made 
 therein. 
 
 We know too little about casting under pressure, 
 except that where there is a good head there is a bet- 
 ter chance of sharp castings than where there is but 
 little. As to artificially creating a high pressure, so 
 as to drive sluggish metal into the fine fines of the 
 mold, and to drive out as much as possible of the 
 gas which would otherwise form pores and even 
 blow-holes, there has been too little done and too 
 little tried. 
 
 There should be a method by which castings 
 could be made as sharp with iron, steel, and copper 
 as are now attained in type-casting. 
 
 In attempting to cast silver one encounters diffi- 
 culties almost without end. Some day the secret 
 will be discovered, just as it has been with copper 
 by a select few, who are very careful to keep it to 
 themselves. 
 
 There are few of us who have seen good copper 
 castings; fewer yet who have made them. When 
 one looks at the complicated pieces which are used 
 in the commutators of dynamo generators and mo- 
 tors, and which, when they are not drop-forged, — 
 which only pays where there is a very large quan- 
 
Foundry Practice 89 
 
 tity to make, — must be laboriously sawed and filed 
 out from the plate, one must admit that copper cast- 
 ing would come into play here. And there are hun- 
 dreds of other possible applications. The best cop- 
 per casting would be one which would be as dense, 
 and as conductive to electricity, as the electrolytic; 
 would in this instance weigh about 20 per cent more 
 from the same pattern than what we usually get, 
 have a salmon pink instead of the usual deep red 
 color, and a fine crystalline fracture like that of stat- 
 uary bronze. It would also have a much greater de- 
 gree of toughness than ordinary porous castings. 
 
 The ancients — that is, the 'way-back ancients 
 — are said to have been able to harden copper. The 
 author neither admits nor denies this. It is possible. 
 The art would be very well worth rediscovering. 
 
Chapter XIII. 
 HEATING 
 
 An oil-stove which will permit of broiling, can be 
 used in the open air or where there are heavy 
 draughts, and which may be kept burning ten hours 
 at a time should find hundreds of thousands of pur- 
 chasers. 
 
 There is need for the invention and manufacture 
 of an appliance to be put in an ordinary stove or 
 kitchen range, by which, without an offensive smell, 
 petroleum may be burned right in the grate used at 
 other times for coal. 
 
 The superheated steam oven is an invention which 
 should pay to develop into practical form for every- 
 day use by ordinary baking-establishments. The 
 idea of baking by steam has been tried and found 
 veiy successful in large institutions and on ocean- 
 liners. Who will give the baker around the corner, 
 at a reasonable price, an oven which will run by 
 steam only and give better satisfaction than the 
 present coal-heated or wood-heated affairs ? 
 
 The use of fuel brikets (what is the use of spelling 
 this word with a q and two t's?) is on the increase 
 in industrial establishments, and for locomotives 
 and steamers; and for the household the new fuel 
 is making steady, if rather slow, progress. One 
 obstacle is that housekeepers are too well satisfied 
 [90] 
 
Heating 91 
 
 with their self-feeding stoves for small coal to be 
 willing to use a fuel that has to be fed in from time 
 to time. The moral is that an arrangement by which 
 brikets of two pounds' weight could be fed contin- 
 uously all day long into a small stove would be 
 desirable. 
 
 The manufacturers of brikets of anthracite culm 
 — and more particularly those who are not yet such 
 manufacturers, but would like to be — seek a bind- 
 ing-material which shall be as effective as pitch, 
 but would not smoke nor make the stokers' eyes 
 sore, and which would also be cheaper. Clay has 
 its advantages from the point of view of the man- 
 ufacturer, as it weighs heavily but costs next to noth- 
 ing; but housekeepers find out after an extended 
 use, and power-users right away, that there is too 
 much ash where it is used as a bond, and that it 
 does not pay to give the same price per ton for clay 
 as for combustible. Rye flour has been proposed, 
 and even used, but it is not safe to presume that its 
 employment would be possible on any very extended 
 scale, under all harvest conditions. 
 
 There are all sorts of meters — their reputation 
 is not of the very best. Only steam-meters are not 
 proverbially liars, because they are too few to have 
 become proverbial. Those that are in existence 
 have but limited use, are too complicated and ex- 
 pensive, and sometimes require a mathematical 
 education to enable one to know what the measure- 
 ment is. 
 
Chapter XIV. 
 
 LIGHTING 
 
 Those of us — and who is there that has not ? 
 — who have grumbled at the size of the monthly 
 gas bills would be glad if they could make gas at 
 low cost without increasing the rate of fire insurance 
 on the premises, and without finding the quality of 
 the gas (or so-called gas) delivered to vary with 
 the temperature of the outside air. The household 
 gas-machine that will do this is not yet in existence; 
 if it is, it is manufactured in strict confidence in 
 some spot to mortals unknown. 
 
 If you cannot get up the desired gas-machine, — 
 so called because it delivers a carburetted vapor, 
 which is no gas at all and stratifies when the tem- 
 perature falls to zero or even sooner, — then invent 
 a gas-meter that will not be as inaccurate as those 
 known to all of us, and which for all that are so 
 readily tampered with by dishonest consumers. The 
 test of the accuracy of such meters is that the 
 sum of the readings of all the meters in a fine should 
 very nearly equal, but should never exceed, the 
 reading of the station meter. But there are cases 
 where the total of the readings of the customers' 
 meters has been greater by twenty per cent than 
 the reading of the station meter through which 
 passed all the gas which the customers received. 
 [92] 
 
Lighting 93 
 
 There have also been cases where no leaks were 
 found, and the drip-pots were clean, but for all that 
 the customers' meters would not account for more 
 than three fourths of the gas delivered. Is it any 
 wonder that the gas-meter rivals the telegraph in 
 its reputation for untruth? 
 
 In any tall building the gas-pressure in the upper 
 stories is apt to be greater than in the lower; and 
 those who live next or near to a church or theatre 
 usually notice their gaslights flare more or less when 
 many lights in the neighborhood are extinguished. 
 This is no more than should be expected from a 
 fluid like gas, lighter than air and flowing through 
 pipes, under pressure from a weighted reservoir. 
 The problem is how to stop the flaring, and how to 
 give each burner its share of gas under that pres- 
 sure which will produce good combustion at an 
 economical rate. Having a pressure-regulator to 
 keep the supply to the house equal at all times pre- 
 vents the variation of pressure when the lights in 
 the neighborhood are extinguished ; but in tall build- 
 ings there remains the difficulty of the upper stories 
 getting the most pressure. A pressure-regulator for 
 each story is in this particular a great help, and for 
 hotels or other buildings having many burners on 
 a floor is employed; but for other cases there should 
 be burners which are self -regulating — each inde- 
 pendently of all others. Such have been made, 
 but they have as a rule been too delicate, and have 
 readily clogged with water or deposit. The field re- 
 mains, therefore, practically uncultivated. 
 
94 Hints to Inventors 
 
 Although nearly every six months brings out a 
 new "mantle" for incandescent gas and alcohol 
 lamps, it is generally, among them all, a matter of 
 "tweedledum and tweedledee." Some give a green- 
 ish light, some a reddish ; all are very readily shaken 
 to pieces by the ordinary jars that take place in the 
 average household — by which "family jars" are 
 not meant ; — and most of them gradually coat the 
 chimney with a white deposit which is the bete noir 
 of the housewife, and which indicates a gradual de- 
 terioration of the "mantle." Some are advertised 
 as having been made of "the very best silk thread," 
 which is usually not true, and would be of no im- 
 portance if it were ; for silk ashes are no tougher than 
 blotting-paper ashes, and the only reason that a 
 woven or knitted fabric is employed is to get a man- 
 tle (the Germans call it a "stocking") that has holes 
 in it for the combustion gases to go through. Noth- 
 ing short of fusion of the edges of the lines of alka- 
 line earth which go to make up the structure would 
 add anything to the tensile strength and durability 
 of the latter; but it might be worth while to try and 
 find a compound that would be more resistant to 
 heat and the chemical action of the gas-flame. The 
 hint is thrown out for what it is worth. 
 
 There are devices which will effect the instanta- 
 neous and simultaneous lighting of all the gas-burn- 
 ers in a church or other large public place, but they 
 have so often proved unreliable that no inventor 
 need be discouraged if he has thought of turning his 
 attention in that direction. The trouble with many 
 
Lighting 95 
 
 of such devices is that they have relied too much on 
 the durability of platinum sponge or its equiva- 
 lent. 
 
 The "duty" of the ordinary electric arc lamp is 
 comparatively low, and many of those in use are 
 either tricky, or dangerous, or both. It goes with- 
 out saying that anything new in this line must be 
 simple and absolutely reliable as regards steadiness 
 of burning, even when the current is not constant. 
 
 Is there a good joint for main gas-pipes ? If there 
 is, why is it necessary for the gas companies or the 
 municipalities to send around a gang of men every 
 year or too, to make borings along the pipe line and 
 smell the earth taken up, to find out where the leaks 
 are ? These leaks, which are expensive to the com- 
 panies, must be paid for eventually by the consumer 
 of the gas that does not leak out, and they kill the 
 trees the roots of which are attracted to their neigh- 
 borhood by the proximity of the water-pipes that 
 are usually not far off from the gas mains. 
 
 It would be a great blessing to humanity, and es- 
 pecially to those who work in factories, if there were 
 some cheap and absolutely certain method of clo- 
 sing cocks and valves at a distance, by electricity, in 
 case of an accident or other emergency. Many an 
 accident could be prevented thereby. The falling 
 of a lighted gaselier usually gives rise to a terrible 
 blaze at the free end of the pipe; and the only way 
 to stop this is to cut off the gas supply. To effect 
 this, one often has to go into a dark cellar and hunt 
 around for the cock. Further, the ability to shut 
 
96 Hints to Inventors 
 
 off the gas every morning when it is needed, with- 
 out having to go "down cellar" to do it, would be 
 appreciated in many a household, and such action 
 would save much gas now lost by leaky pipes. 
 
 A material to add to denatured alcohol, by means 
 of which that liquid fuel could be used as an il- 
 luminant without the employment of an incandes- 
 cent mantle, would be very desirable if it caused 
 neither smell nor soot. 
 
 All sorts of attempts have been made to get up 
 incandescent lamps which will burn petroleum or 
 alcohol; but as a rule they occasion much bad feel- 
 ing on the part of those who have to use them. They 
 generally smell badly and require too long to get 
 them in operation; the best of them that the author 
 has seen require at least a minute and a half from 
 the time of applying the match before the mantle 
 is incandescent. This minute and a half is often 
 extended to two and a half, and in any case always 
 seems much longer than it really is. The shops in 
 which such lamps are sold, and in which the atten- 
 dants gravely state that there is no unpleasant odor 
 attending the use of the device, usually smell like a 
 small edition of Hunter's Point. Of course if the 
 petroleum contains sulfur (with an /, according to 
 the Standard Dictionary) there must be a disagree- 
 able odor with any lamp; and it would be unreason- 
 able to expect that the vaporizer would eliminate 
 the sulfur. The same is true of denatured alcohol 
 as at present made; but it is not too much to hope 
 that the denaturing will be effected by a process 
 
Lighting 97 
 
 which will make the alcohol absolutely undrinkable, 
 without making it offensive to the sense of smell. 
 
 The ordinary glass lamp for burning petroleum 
 is breakable, hence dangerous if upset. The metal 
 lamps for the same purpose heat the petroleum, if 
 they are kept burning a long time. A lamp which 
 would not heat its contents by conduction, and which 
 would be practically non-breakable if it fell from a 
 table to the floor, would sell itself. 
 
Chapter XV. 
 
 STEAM BOILERS AND THEIR AP- 
 PURTENANCES 
 
 Power-users will herald the day which gives 
 them a good automatic stoker for their boilers. 
 
 The methods employed to burn "bagasse'' (the 
 refuse of the sugar-cane as delivered from the mill) 
 are crude and should be improved upon. 
 
 The smoke-consumer which will save fuel and 
 lessen the smoke nuisance in those cities where soft 
 coal is burned is yet in the future; and if it will do 
 what is desired of it, and will, in addition, be applic- 
 able to locomotives, there will be in it what the 
 boys on the street call "big money." 
 
 Firing with coal-dust and similar fuel has shown 
 itself advantageous everywhere that it has been 
 properly tried. It can be regulated almost as finely 
 as is the case with liquid fuel. The fuel is cheap, 
 and unfortunately only too generally on hand. If 
 it pays the Germans and French to grind their good 
 coal as it comes from the mines, mix it with pitch 
 or other bond, and press it into fuel brikets, it should 
 pay Americans to use the coal slack as it comes. 
 The mechanism for feeding it into the fire-chamber 
 should not be complicated nor take much power 
 to drive it. And of course, as steam usually has to 
 be raised before shafting-lines can turn, there must 
 [98] 
 
Steam Boiler 
 
 be an arrangement by which the fire can be started 
 and brought to full pitch without the aid of the 
 dust-feeder. 
 
 And the safety boiler! Has the perfect generator 
 of steam been produced ? There are many excellent 
 ones in use and some good ones coming out; but 
 perfection is a long way ahead, and the success of 
 those good ones which are already before the public 
 need not keep any one from bringing out still bet- 
 ter ones. 
 
 The apparatus generally in use to record from 
 time to time the height of water in a steam boiler 
 are too complicated and delicate, and also too dear. 
 Further, many of them are easily made to give a 
 false record. Such an apparatus must be like Cae- 
 sar's wife, above suspicion. 
 
 There are several devices on the market by which, 
 in case a glass water -gage breaks, the steam and 
 water will be automatically shut off by the unbal- 
 anced pressure; but there is in this particular much 
 room for improvement. Some of them do not in- 
 dicate when they are stopped up by scale or dirt in 
 the communicating passages; some have no means 
 of cleaning out such passages from time to time, to 
 prevent their becoming choked. 
 
 The bursting of a live steam-pipe is usually at- 
 tended with great danger to life and limb. This is 
 especially so on board ship. There would seem to 
 be room for a device that would close the shut-off 
 valve next the boiler so soon as a break occurred 
 which would let more steam out than the maxi- 
 
 LOfC, 
 
100 Hints to Inventors 
 
 mum delivery when all engines or other steam-con- 
 sumers were on. 
 
 A good cheap process by which steam boilers 
 could be coated internally with copper after the last 
 rivet and stay-bolt had been put in would add greatly 
 to their tightness, and help in keeping them clean. 
 The failure to cover any one place, however small, 
 would cause galvanic action and corrode the iron 
 or steel more than would take place without the 
 coppering, 
 
Chapter XVI. 
 
 STEAM ENGINES AND APPURTE- 
 NANCES 
 
 The rotary engine which will use steam expan- 
 sively, be durable, and not give trouble from leak- 
 age has not yet been evolved. There is a chance for 
 it yet. 
 
 One of the most important inventions of the last 
 twenty-five years is the steam turbine. It has, how- 
 ever, despite its great advantages of compactness 
 and high speed, the disadvantage of not being re- 
 versible, and of being subject to rapid wear of the 
 blades. These two points are worth looking into. 
 The steam turbine, like all new daily papers and 
 the proverbial mother-in-law, has come to stay. 
 
 A problem which is worth working at is the pro- 
 duction of a mechanical substitute for the fly-wheel 
 on ordinary steam engines or other motors, partic- 
 ularly those running at slow speed. This problem 
 has been practically solved in pumping-machinery 
 by the use of hydraulic auxiliary cylinders, which 
 absorb power and give it out again. 
 
 Can you get up a good device which will auto- 
 matically and instantly stop the engine and all mov- 
 ing parts connected therewith in case any one gets 
 caught in the machinery? 
 
 The same principle that is applied to water-gages 
 [101] 
 
102 Hints to Inventors 
 
 should be applied to sight-feed oilers. Should the 
 glass break, the connection with the steam supply 
 should be shut off, so that no damage could take 
 place by reason of the escaping steam; and the re- 
 placing of the glass should be easily effected. 
 
 There is still need of a good governor that will 
 not change its gait by reason of defective lubrica- 
 tion, or dance when well lubricated, or when loosened 
 up. Nearly all governors that are on the market 
 are designed on the false principle that they and 
 the engine which they govern must first go extra 
 fast in order to go more slowly. Very often they are 
 too dependent on the fly-wheel, so that for small 
 changes of load they might as well not be there; the 
 fly-wheel alone takes care of the variation. The 
 perfect governor should keep the speed of the motor 
 within one per cent of the normal to which it is set, 
 whether the engine has normal load, or extra heavy 
 load, or is running with no load at all ; and this reg- 
 ulating-power should be maintained in the face of 
 a ten per cent variation in the steam-pressure either 
 side of the normal. To particularize: when with 
 half load and normal steam-chest pressure of seven 
 atmospheres the normal speed of the engine is one 
 hundred turns a minute, this speed should not be 
 raised more than one turn a minute with the load 
 thrown off and under eight atmospheres; and con- 
 versely, with full load and only six atmospheres pres- 
 sure the speed should not drop below ninety-nine 
 revolutions per minute. Such changes are common 
 in electric-lighting plants. Those in boiler-pressure 
 
Steam Engines 103 
 
 should not occur, but those of load ace inevitable. 
 The presence of a good healthy steam-hammer in 
 a shop will drop the boiler-pressure very promptly. 
 
 The author believes that the future governor will 
 be of the dynamometer type; that is, that it will 
 operate by reason of changes in load, before the 
 change in speed has taken place. 
 
 It is strange that the steam road-wagon has been 
 so little developed. Self-propelling steam road- 
 rollers are common enough, and some of them act 
 as traction-engines also on good ;bads; but the 
 steam carriage for ordinary roads is of the future. 
 Perhaps the naphtha-launch motyr idea can be 
 adapted to service in our ordinary streets and high- 
 ways. 
 
Chapter XVII. 
 INTERNAL COMBUSTION MOTORS 
 
 Gas turbines are only in their earliest infancy. 
 One thing that retards their growth is the lack of 
 sufficient cooting-capacity for the internal portions. 
 
 Although tie motor manufacturers have done 
 much in the way of delivering small high-speed 
 motors suitable for automobiles and boats, the aero- 
 nauts seem to think that the limit of lightness and 
 speed has not )%t been reached, and they demand 
 further progress £& these two lines. As this class of 
 customers seem yo be able to pay fancy prices, and 
 as several governments are interested in the prob- 
 lem of dirigible balloons, there should be sufficient 
 inducement to inventors to produce what is called 
 for. 
 
 Despite the probability that the alcohol motor 
 will be introduced in large quantities as soon as the 
 cheap production of denatured alcohol is an accom- 
 plished fact, and despite also the fact that the alco- 
 hol motor has the great advantages of being more 
 cleanly than the petroleum motor, and thermically 
 more economical, because operating with a tenfold 
 instead of only a fourfold compression, there is still 
 room for thousands of petroleum motors in districts 
 where the alcohol cannot be delivered at a low price, 
 but which are right at the sources of petroleum. 
 [ 104 ] 
 
Internal Combustion Motors 105 
 
 Besides, no one knows in what manner the petro- 
 leum kings will meet the new competition. If de- 
 natured alcohol is freed from government tax in 
 order to permit and encourage its use for power- 
 generating, there is no reason why the petroleum 
 price should not b^ cut down to cover the competi- 
 tion. The gas-works accord a special price for 
 lighting-gas used in motors, and petroleum can be 
 sold in the same way. 
 
 In connection with the invention of a good pe- 
 troleum motor there is an excellent opportunity for 
 the introduction of a small, light, high-speed motor 
 for either petroleum or alcohol (not for both, as the 
 two materials require different handling in order 
 to be burned economically) to be used in the pro- 
 pulsion of street-cars. Here the noise must natu- 
 rally be reduced to a minimum, and it would seem 
 as though air-cooling was the only means available 
 — or, at least, that it must be relied on as far as it 
 will go. A speed of seven miles on levels would be 
 sufficient for most cases, although there are places 
 where ten would be welcome. There must be a re- 
 serve of power for use in starting the load on curves 
 and up-grades; this may perhaps be done almost as 
 well by a purely mechanical method as by having 
 extra cylinder power. 
 
 There are many households where a tiny gas or 
 alcohol motor could be used to advantage if it did 
 not make too much noise. One fourth of a horse- 
 power would suffice, and the motor should not per- 
 mit of adjustment by the owner. 
 
Chapter XVIII. 
 TRANSMISSION 
 
 There are on the market flexible shafts which 
 run only one way. It often happens that this is just 
 the inconvenient direction of rotation. It does not 
 take any great degree of invention to make them left- 
 handed instead of right-handed, but there might be 
 some in getting up one that would run equally well 
 in both directions and not loosen up after a few 
 months' use. 
 
 There are many more or less ingenious and prac- 
 tical mechanisms for changing the speed and direc- 
 tion of motion of a driven shaft, but some are too 
 complicated and some are too clumsy, while a very 
 common fault is that those which change the speed 
 do not change the direction, and vice versa. Mechan- 
 ics would welcome a device by which one shaft could 
 be driven from another by a simple, cheap, and 
 compact device that would give a wide range of 
 speed and also be reversible, and which, further- 
 more, could be adjusted while running, to effect the 
 desired change or reversal. 
 
 There is still place for a substitute for the stepped 
 pulley (miscalled "cone pulley") for varying the 
 speed of the driven mechanism by a shaft of regular 
 speed. Most machines that are driven by a stepped 
 pulley have only three speeds. It very often hap- 
 [106] 
 
Transmission 107 
 
 pens that these speeds are not sufficient in number, 
 and further, that they are not the most desirable 
 ones; that is, the character of the varying work 
 would demand five or six speeds, while those fur- 
 nished are either too slow or too fast. The friction- 
 devices offered to replace the stepped pulleys are 
 generally too heavy and too complicated, or they 
 slip where they should drive and stick when they 
 should release. The Evans friction belt-pulleys are 
 really conical, and offer as many speeds as can be 
 called for between the maximum and the minimum; 
 but their extremes are not wide enough apart, and 
 the pulleys are too heavy and too expensive. Further- 
 more, they are not readily obtained. Outside of two 
 cities, the author has never found a dealer who 
 could supply them. 
 
 Supply-dealers seem to have no good belt-stretch- 
 ers which will insure the tension on the belt being 
 the same on both edges, and that this tension will 
 not be too great for the lacings or even for the jour- 
 nals. The necessity of having the tension the same 
 on both edges cannot be too strictly insisted upon, 
 if the belt is to run straight. 
 
 There is place for a transmission on dynamom- 
 eter light enough to be carried by one man, and 
 which can be used in connection with belt-pulleys 
 of all diameters and speeds likely to be found in 
 the average machine-shop or factory. It should 
 preferably give a reading which gives or represents 
 the horse-power directly, without necessitating two 
 multiplications to attain the desired result. In any 
 
108 Hints to Inventors 
 
 case, no more than one multiplication should be 
 necessary. 
 
 Strange as it may seem, there has not yet been 
 put upon the market a good ball-bearing or roller- 
 bearing for engine-shafts and machinery generally. 
 The manufacturers of bicycles seem to have got 
 what is wanted, but in larger sizes the field is yet 
 open. 
 
Chapter XIX. 
 POWER IN GENERAL 
 
 Turbine governors have not been given the atten- 
 tion which they deserve. The decreasing amount 
 of water which streams in new countries deliver, 
 by reason of the cutting-down of the forests, calls 
 for supplementing water-wheels with steam engines. 
 This necessitates very careful governing of both. 
 The same cause which diminishes the average power 
 of a stream makes it more liable to floods in spring- 
 time, when the snow melts; and here again all tur- 
 bines need governors. The increasing use of electric 
 lights, even in the forest where lumber is cut, makes 
 regulation of the turbine or water-wheel which drives 
 the dynamo all the more desirable. 
 
 Solar motors could be very well used for pump- 
 ing water in those countries where the sun is very 
 hot, and running water scarce. 
 
 So far the accumulation of power has had too 
 limited an application. There is a great range be- 
 tween the tiny pocket battery and the immense ac- 
 cumulators used in plants for electric light and 
 power; but not only the number of applications, but 
 the number of modes of application, are too limited. 
 What is needed is a method of conveniently and 
 economically accumulating the power of the light- 
 ning, the wind, the tides, freshets, and the heat of 
 
 r 109 1 
 
110 Hints to Inventors 
 
 the sun. This is a wide range, and the means of 
 accumulating the various sorts must be correspond- 
 ingly various; but the general problem calls for 
 the accumulation of electricity. In the first case 
 there must be a "step down" unparalleled in the 
 history of transformers ; in the second and third there 
 is already present mechanical power which must be 
 converted into electricity in order to be well stored 
 and conveniently distributed; and in the fourth case 
 heat is present and must be converted into electric- 
 ity only after it has been made to take the form of 
 mechanical energy. 
 
Chapter XX. 
 MOTOR CARS AND BICYCLES 
 
 Just as the speed and lasting powers of a horse 
 are limited and measured by the condition of his 
 front feet, so with the motor-car: the tire limits and 
 measures what it can perform. Motor manufac- 
 turers have done wonders — more than was ex- 
 pected of them; and tire manufacturers have also 
 done wonders, but it has been expected of them 
 that they set aside the laws of inertia and friction, 
 and that they have not done and will not do. The 
 shocks incident to the jumping motion experienced 
 at high speeds, even on good roads, are sufficient 
 to burst the strongest and most thoroughly air- 
 cushioned tires; there is no rubber or canvas that 
 will resist broken glass and bottles, and there is no 
 way by which the momentum attained by a car 
 when going at high speed in one direction can be 
 arrested without the car sliding or tipping. The 
 best that the manufacturer can do is to make tires 
 which shall lessen the sliding and to a high degree 
 withstand the wear. If the tire can be given a good 
 grip on the road surface, the driver will have some 
 show to turn the machine, even although the road 
 is not elevated on the outer edge of the curve. And 
 that is all that the tire manufacturer should be 
 
 [ mi 
 
112 Hints to Inventors 
 
 asked to do — provide a tire that will stand rough 
 usage and dig in. 
 
 The most frequent cause of pneumatic tires (what 
 a misnomer!) is the fact that India rubber as used 
 therein is not air-tight under great pressure. There 
 may be some preparation which would make it so; 
 if there is, there is money therein. 
 
 There are several makes of motor-cars in which 
 it is almost impossible to tell from the driver's seat 
 how much benzin or alcohol there is in the tank. 
 For these special machines there is a loud call for 
 some device which would attain the desired end. 
 It would be a convenience on long tours, and facil- 
 itate matters at custom-houses on the frontiers. 
 
 There are several sorts of sparking-apparatus on 
 the market for benzin and alcohol motors, but there 
 are few that are satisfactory, especially where the 
 driver is not used to electrical apparatus. Some- 
 thing more reliable and more easily adjusted, re- 
 paired, or replaced is demanded. 
 
 Singularly enough the motor-car has become a 
 luxury and a convenience before being adopted 
 to any great extent for common work. There should 
 be an even greater market for automobiles for farm 
 and other hauling purposes — to say nothing of 
 the army in countries burdened with such a thing 
 — than at present for sporting and pleasure-seek- 
 ing purposes. They would not bring such high 
 prices per pound, but there would be more pounds 
 per piece, and more sold. And the purchasers 
 would be very much less exacting as to performance. 
 
Motor Cars and Bicycles 113 
 
 Most of them would know very little as to the ca- 
 pacity, and almost nothing as to the duty. They 
 would want something that would carry a load or 
 haul one, or both, and that could be run by a hired 
 man and repaired by a country blacksmith — that 
 is all. This machine should be able to run on ordi- 
 nary to miserable roads and occasionally cross a har- 
 rowed, if not a plowed, field ; must be a good grade- 
 climber, and have a spark-arrester; and if possible 
 it should be able to act as a driving-engine for a 
 thresher or a cutting-machine. 
 
 Among the other improvements that would be 
 welcome on automobiles would be a steering -ap- 
 paratus which would wear equally in all parts, and 
 which would have the distinguishing feature that 
 for short turns it would have a stronger leverage to 
 turn it than where there is only a slight swerve. 
 Another feature should be that the steering-gear 
 should stay fixed in the last position in which it is 
 placed, so that if the driver's hand is taken from 
 the wheel the machine could not be thrown off its 
 course by an obstacle, as a stone in the road. 
 
 There is no particular pleasure caused by a motor- 
 car making a noise in running. Sometimes the noise 
 is caused by the exhaust, and sometimes by the gears. 
 The exhaust is the greatest sinner in this particular, 
 and a good muffler would be appreciated by the 
 manufacturers and owners — to say nothing of " the 
 man in the street." 
 
 While there are all sorts of instruments by which 
 the power developed by steam engines — including 
 locomotives — and water-wheels may be accurately 
 
114 Hints to Inventors 
 
 measured and even recorded, the automobile is at 
 present devoid of any contrivance which will give 
 an idea of how much power is developed at various 
 speeds and with various loads, on different kinds of 
 roads, and in running on level stretches or climbing 
 hills. - 
 
 But what would interest the owners of an auto- 
 mobile still more than a power-meter or dynamom- 
 eter would be a recording-apparatus which would 
 prove at what speed the car was going at any partic- 
 ular moment. This would do away with all dis- 
 putes with "auto-cops" and others interested in 
 fining drivers for excessive speed, and would also 
 prevent disputes with automobile-cab drivers as to 
 whether they were making the legal time or not. 
 
 Another attachment for fast motor-cars would 
 be a speed-regulator which would not only ^x the 
 number of turns per minute made by the wheels, 
 but also set a limit to the speed at which the machine 
 could possibly be driven. This would wipe out of 
 existence many controversies as to the speed. If 
 the owner of a machine locked the device to prevent 
 it being driven more than at a certain speed, his 
 chauffeur, or whoever he may happen to let, lend, 
 or otherwise confide it to, could not exceed that 
 speed and get him into scrapes with the "minions 
 of the law." 
 
 As a rule, the question as to whether or not a lady 
 may ride a bicycle — and especially a man's wheel, 
 which is much stronger, safer, and more easily driven 
 — has its basis in a false sense of modesty, which 
 
Motor Cars and Bicycles 115 
 
 after all is a relative term, as witness the attitude of 
 the Japanese as regards exposure of the neck and that 
 of the Turks in the matter of showing the face. 
 Further, the whole affair is too much bound up with 
 the clothes question. Be that as it may, no one can 
 argue a lady out of her ideas as to what is modest 
 and proper — and perhaps it were better so. But 
 what can be done is to afford those ladies who are 
 opposed to the bicycle (or who are controlled by 
 others who are in such opposition) an opportunity 
 for transporting themselves from place to place on 
 a wheel which would give Mrs. Grundy not the 
 slightest chance for talk. A wheel propelled by the 
 arms, and made as well in all particulars as the aver- 
 age bicycle with pedals, would find good sale — 
 and also act as an advance agent in winning to the 
 use of the pedalling bicycle many who now go only 
 on " Shanks' mare." 
 
 There are offered for sale no end of locks for 
 bicycles. Some of them are so complicated that 
 they get shut and refuse to be opened, even by the 
 authorized owner. Others are so flimsy that a good 
 pair of cutting-pliers, or a healthy twist with both 
 hands, disposes of them. Some are "confidence 
 locks" — one can always be confident of being able 
 to pick them with a hairpin if the key be lost. There 
 should be ingenuity enough in the country to pro- 
 duce something better, and at a price which would 
 not be prohibitive of large sales. 
 
 The numerous cases of unauthorized persons 
 taking a motor-car out of the garage, or running off 
 
116 Hints to Inventors 
 
 with it in the open street in the absence of a care- 
 taker, should make inventors look out for a lock on 
 the starting-gear, to prevent any one but the duly 
 authorized person setting the car in motion. 
 
 Perhaps least, but at any rate last: the average 
 car raises too much dust. This does not annoy the 
 occupant, but it does help to raise prejudice against 
 the motor-car on the part of those not so favored 
 as to possess one. The cause of the dust-raising is 
 usually in the design of the frame and running- 
 gear, as it will be noted that some cars raise no dust 
 where others at the same speed are insupportable 
 to those behind them. 
 
Chapter XXI. 
 STREETS AND ROADS 
 
 An improved roadway is needed in this climate: 
 something that will wear as well as stone, be as easy 
 to pull on as asphalt, and give the horses' feet a good 
 grip so that they will not slip even in rainy weather. 
 
 A good enough monolithic street pavement has 
 not yet been laid. Cobblestones would vanish if 
 we had something perfect and in one piece to take 
 their place — something which would give the 
 horses' feet a good grip while allowing the wheels of 
 vehicles to run smoothly without great resistance or 
 noise. 
 
 There is a great difference between being smooth 
 and being level or flat. There are many asphalt 
 pavements — both on the roadway and on the 
 trottoir (or footway, an it please you better) — 
 which have been "slicked" by hand until they are 
 smooth; but every rain shows by the puddles that 
 it leaves that there are sinks therein. A machine 
 to smooth down the hot asphalt as soon as it is laid, 
 so as to leave the surface free from local depressions, 
 might prolong the life of the pavement, and would 
 certainly add much to the comfort of the public. 
 
 And while on the subject of asphalt, the attention 
 of inventors might be drawn to the desirability of 
 a compound to take the place of the present mix- 
 
 t "7] 
 
118 Hints to Inventors 
 
 ture, which would be smooth enough as regards the 
 wheels, and yet give the horses' hoofs some little 
 hold, especially in wet weather, so that it would not 
 require sanding — which latter operation is expen- 
 sive, and makes dust and mud after the rain is over 
 and the street dried off. 
 
 There is no good machine for ramming paving- 
 stones. It should be so light that it could be drawn 
 by one horse on ordinary unpaved streets, and 
 should be driven by a steam engine or an internal 
 combustion motor. 
 
 Six or eight husky men can ram paving-stones 
 pretty firmly; but getting the blocks out again is 
 slow work, if they happen to be a good fit when they 
 are put down. What is needed to supplement the 
 ramming-machine — and it could be used even be- 
 fore this makes its appearance — is a stout and 
 practical tool to take the stones up, as for instance 
 where it is necessary to remove one every five feet 
 along the line of a gas-pipe, for the purpose of ma- 
 king borings to test for gas-leaks. 
 
 There is no city in the world which has any con- 
 siderable amount of snowfall that is provided with 
 adequate means of getting the snow and the accom- 
 panying dirt out of the way promptly and at slight 
 expense. Until such method is produced, traffic in 
 our greatest cities will suffer congestion or com- 
 plete stoppage every time there is a heavy snow — 
 particularly if it come with no warning. 
 
 And the street-sweeper. Cannot some bright 
 American bring forward a machine which shall do 
 
Streets and Roads 119 
 
 more than simply brush the dirt to one side or the 
 other and leave thin windrows ? There is demanded 
 something which will take the dirt up bodily and 
 put it into a box to be carried with it until the ma- 
 chine has reached the end of the route, or the box 
 is full. 
 
 The horseshoe of the present is an abomination. 
 There needs to be something which will save the 
 hoof from undue* wear and breakage, while at the 
 same time permitting elasticity of movement when 
 the weight of the body is alternately borne upon 
 and taken from it. The present system of shoeing 
 is not humane, nor is it economical. 
 
 The horseshoe and the perfect roadway for the 
 horse's foot to travel upon having been provided, 
 there should be produced a better wagon-wheel 
 than at present exists. While American wheels are 
 the best in the world, American roads are in the 
 same or a greater proportion the worst; and there is 
 needed a wheel which will have a strong yet elastic 
 tire and be then less easily buckled than those which 
 we have at present. 
 
 The safety appliances in front of tram-cars, to 
 prevent foot passengers being run over, might have 
 been sufficient in their day, — which was the day of 
 horse traction, — but now that cable and electric 
 traction are the rule they are highly inadequate. 
 Here we have increased danger with no improve- 
 ment in the precautions for safety. It is true that 
 many tram-car companies prefer to pay damages 
 for accidents rather than equip all their cars with 
 
120 Hints to Inventors 
 
 safety devices; but here the fault lies not any more 
 with the companies than with the public at large, 
 and their representatives in city councils in partic- 
 ular; for these latter are apt sometimes to demand 
 impossibilities, and have also been known to have 
 personal interest in inventions that are either worth- 
 less or cost by far too much in proportion to their 
 real value. The author is of the firm belief that 
 when inventors do what is expected of them the 
 tram-car companies will do their duty. 
 
Chapter XXII. 
 BUILDING 
 
 One of the best opportunities for inventors to 
 display their genius is in the production of a ma- 
 chine for laying long courses of bricks in straight 
 walls. It is only required that it shall produce an 
 ordinary bond, and have some slight adjustability 
 for different sizes of bricks — not in the same wall, 
 but as between one wall and another; although for 
 Germany even this is not necessary, as, there, bricks 
 must be of the regular standard dimensions pre- 
 scribed by the authorities for the whole country. 
 
 It goes without saying that the machine is to lay 
 the mortar. Hand-pointing would be permissible. 
 The machine would only have to satisfy the require- 
 ments of contractors having long reaches of straight 
 wall, with openings for windows and doors as re- 
 quired. These the machine would have to arrange 
 for, just as a typewriting-machine provides spaces 
 between the sentences. Hand-work is at the rate of 
 from fifty to one hundred and twenty bricks per 
 hour, according to the size of the bricks, the skill or 
 the workman, and whether he is paid by the day of 
 the thousand. It would be sufficient if the machine 
 would lay double the maximum capacity of a man; 
 even one which would do only one hundred and 
 [ 121 ] 
 
122 Hints to Inventors 
 
 fifty an hour would be welcome, as freeing the mas- 
 ters from the tyranny of the unions, and of course 
 incidentally enabling work to be done where skilled 
 laborers could not be had at any price. 
 
 The heavy and costly scaffolds which are called 
 for by law in some countries, and by custom in 
 others, for use in painting the exterior of buildings, 
 are too cumbersome, and prolong the work too long. 
 Something should replace them. 
 
 An arrangement is called for which would satisfy 
 the building authorities, where such exist, and which 
 would enable the house-painter to paint a wall with- 
 out calling in the help of so many laborers. Now- 
 adays, the scaffolds used in Germany, for instance, 
 take five men a day to put one up and three men a 
 day to remove it where the actual work of painting 
 only takes two men two days. The first requisite is 
 that it shall be absolutely safe; that is, it must not 
 fall down of its own motion, nor be readily knocked 
 down by a runaway team; and there must be no 
 opportunity for the workmen thereon falling off 
 by inadvertence. 
 
 Roofing-paper — too often miscalled "felt" — is 
 needed, for temporary buildings and for the under 
 covering of permanent ones, that shall be thoroughly 
 water-proof and fire-proof, — that is, highly spark- 
 proof; incombustibility is not called for, and while 
 being easily laid, it must have considerable resist- 
 ance to tearing. Cheapness must be among the 
 requisites. 
 
 A roof made of such paper felt, or whatever it 
 
Building 123 
 
 might be called or miscalled, would go well for 
 temporary exhibition buildings, wharf sheds, etc. 
 
 Hardly a month goes by without some architect, 
 Common Council, or other person or body calling 
 for a fire-escape that can be permanently attached 
 to the building, but when not in use shall lie folded 
 down flat against the wall. When needed it must 
 be readily opened out to the position for use, and 
 not fold back again until this is required. It must be 
 so constructed that it would not require an athlete 
 to use it, even in sleety weather; and should be capa- 
 ble of being brought into position from the build- 
 ing itself without affording burglars extra facilities 
 for entering the windows which it served. 
 
 It ought not to be very difficult to produce a ma- 
 chine which would paper the walls and even the 
 ceilings of ordinary rooms, and do it better than is 
 now done by hand — which, unfortunately, is not 
 saying much. The advantage of the machine should 
 not he so much in the amount of work which it 
 would do in an hour, but in the greater smoothness 
 with which it laid the paper. 
 
 One of the most prolific subjects for patents in 
 countries where hinged shutters and sash are the 
 rule should be proper fastenings therefor; but, un- 
 fortunately, the bill is not yet well enough filled. 
 The desired fastening should hold the shutter 
 closed against any attempt to open it from without, 
 and open at any desired angle. 
 
 The spring-balanced roll-shutters for shop win- 
 dows, that roll up so easily because the spring so 
 
124 Hints to Inventors 
 
 nearly exactly balances the weight of the slats, have 
 earned a great deal of money for the inventor and 
 manufacturers; but who shall say that they are per- 
 fect ? And who could say that there is only one way 
 of accomplishing the result — or that the already 
 patented way is the best one? The history of all 
 invention is to the contrary. 
 
 There are some quite good roll-shades for balco- 
 nies — designed to keep off the wind and to some 
 extent the sun, at any rate when its rays are nearly 
 horizontal. They are very much too expensive, 
 and often much too clumsy; and furthermore, their 
 length is fixed. There is no means of joining two 
 or more sections to make a continuous screen; and 
 sometimes this would be very desirable. 
 
 No one can claim, with any great hope or chance 
 of being believed, that the present system of holding 
 window-panes in the frames with putty is handsome. 
 It certainly is much more convenient than the old 
 way of soldering lead rims around the pieces; but 
 modern artistic building would take kindly to this 
 latter again if it were not so expensive. Is there a 
 possible way to hold the panes water-tight and air- 
 tight in any sort of frames, and produce a better 
 artistic effect than the putty plan ? 
 
 Sir Boyle Roche, when member of Parliament, 
 said, among other things which have been handed 
 down to us as good specimens of thoroughbred 
 Irish bulls, that a man could not be in two places at 
 once, barring he was a bird! Those of us who have 
 had to get up in the middle of the night and close 
 
Building 125 
 
 the shutters or the hinged windows by reason of a 
 sudden rain-storm, or who have come home and 
 found that in their absence the rain has done dam- 
 age by reason of open windows, will see just why a 
 demand has been expressed for an arrangement by 
 which the shutters or the sash would close auto- 
 matically when a heavy rain came on. Things which 
 were apparently more impossible are being done 
 every day. 
 
 There are door-closers and door-closers; but the 
 perfect one has not yet appeared. The most efficient 
 part of many of them is the advertisement that they 
 give their makers under the pretext of notifying the 
 public that it is not necessary to take the trouble to 
 close the door, as it is provided with Smith and Jones' 
 celebrated patented automatic harmonic door-clo- 
 sing device. The trouble with most of them is that 
 they do not effect the final and thorough closing, 
 unless they do it with a bang. Others require that 
 one possess an intimate knowledge of the laws of 
 the parallelogram of forces as applied to the toggle- 
 joint, in order to put them on properly. 
 
 The sash-cord and pulley method of holding win- 
 dows at any height is very crude, and inventors 
 might as well profit by that fact and bring out some- 
 thing which will be better. 
 
 Some day somebody will produce a system of gla- 
 zing without putty, and will receive the thanks of all 
 of us and the dollars of many of us. 
 
Chapter XXIII. 
 KERAMICS AND GLASS-MAKING 
 
 Although hundreds of brick-machines have been 
 produced, and brick-machines are demanded by 
 manufacturers, there is none which has been very 
 generally adopted. Verbum sap. 
 
 Terra-cotta pipes of from six to ten feet in length, 
 and with smooth glazed inner surfaces, would be by 
 far better from many points of view, for smoke-flues 
 and water-closet pipes in houses, than the short 
 lengths now used, which call for so many joints, 
 which the settling of the building may make no longer 
 tight. A process by which such pipes could be made 
 and burned without getting oval or crooked would 
 be worth trying to attain. 
 
 Fancy-colored (not glazed) bricks are demanded 
 and not produced. Which of my readers will bring 
 them out? 
 
 A good process for enamelling building-bricks 
 on only one face, or on two, would take well. At 
 present the results attained leave much to be desired 
 both as regards the appearance of the bricks and in 
 the matter of cost of manufacture. There are by 
 far too many "seconds" both before and after burn- 
 ing; and these are hard to dispose of, and even to 
 use in many ways. Once covered with the colored 
 slip, no one likes to have them among ordinary 
 [ 126] 
 
Keramics and Glass-making 127 
 
 bricks, as this increases the cost of laying except 
 for partition walls, or other places where the varie- 
 gated appearance of the mixture of kinds would 
 make no difference. 
 
 In nearly if not quite all brick-machines of the 
 "sausage," "bar," or "screw" type — that is, 
 those in which the clay is pugged and forced out 
 through a die into a long bar which is then cut into 
 proper lengths to make one brick each — there is 
 encountered the great fault that the wire or the 
 knife that cuts the bar leaves on two edges a pro- 
 jecting fin, and, further, is apt to score the face along 
 which it passes. This is particularly the case where 
 the clay has stones or roots therein, as they are 
 dragged along with the wire or the knife, and ruin 
 the appearance of the brick. To attain a smooth 
 cut without fin on the edges or scores on the face 
 would be well worth trying for. Whether this re- 
 sult was attained by avoidance of the fin or scores, 
 or by smoothing them off automatically, would 
 make but little difference in the finished product 
 ready to dry and burn. 
 
 In making so-called " china" ware, the mass is sub- 
 ject to great shrinking in drying, and no matter how 
 slowly this takes place, there are apt to be cracks 
 formed in the edge of large flat pieces such as meat 
 dishes and even the larger sizes of plates. The 
 shrinkage amounts to about ten per cent in diameter, 
 and this has to be allowed for in making the plaster 
 molds for the mass. If, now, there could be some 
 
128 Hints to Inventors 
 
 addition to the mass to lessen this shrinkage, it 
 would be welcomed by the potters. 
 
 Porcelain factories very much need a process by 
 which to free the china clay (kaolin is the proper 
 name) from iron oxide, which occasions discolora- 
 tion of the ware, so that many clay deposits are ab- 
 solutely useless for white ware, although in the mat- 
 ter of toughness and smoothness they are better 
 than those now employed for white ware merely be- 
 cause they are absolutely free from iron. 
 
 If some one would invent a process of glazing 
 ordinary pottery without the danger of lead-poison- 
 ing which is now one of the drawbacks in the in- 
 dustry, he would earn the gratitude of the workmen 
 and manufacturers. 
 
 The mechanical manufacture of lamp-chimneys, 
 and particularly of those intended for lamps with 
 tubular wicks, is greatly to be desired. The chim- 
 neys specially mentioned have a shoulder, which 
 increases the cost of manufacture by hand. 
 
 Is the idea of flexible glass too fantastic for the 
 modern inventor? If the ancients could harden 
 copper — which is more than we can do — the fact 
 that a thing has not been done in modern days should 
 be no proof to us that it cannot be done. 
 
 The secret of making " Scotch" gage-glasses seems 
 to be too much of a monopoly. 
 
j 
 
 Chapter XXIV. 
 I 
 
 TEXTILE* 
 
 The cactus and other Mexican fiber-bearing plants 
 have not yet been made to yield up their fiber for 
 textile purposes at a cost low enough to make it 
 worth while to work them. 
 
 A good substitute for horsehair (as, for instance, 
 for making cloth used in the lining of men's coats) 
 would sell well, as horsehair is dear and not long 
 enough to be easily woven. Further, the sharp- 
 pointed ends of the hair come through the garments 
 stiffened with the cloth. 
 
 A good substitute for the fibers of the broom- 
 plant (Ginesta germanica) would be welcomed, as 
 the broom fibers are difficult to free from the fleshy 
 portion, and to clean. 
 
 Covering linen and cotton threads with a solution 
 of silk, so as to produce an effect quite closely re- 
 sembling that of silk itself, has become a very im- 
 portant and paying industry; but by reason of the 
 popularity of the product there is a demand for still 
 further steps. At present the sheen of the fabrics is 
 inferior to that of silk, and naturally it lessens with 
 wear. The time will come when there will be dis- 
 covered a substitute for silk that will be cheap 
 
 * See also the chapter "Inventions for which Prizes Are 
 Offered." 
 
 [ 129] 
 
130 Hints to Inventors 
 
 enough to permit its being more thoroughly incor- 
 porated into the threads. There is a process which 
 very closely imitates the dissolved sill; effect, but 
 dispenses entirely with the latter material; and in 
 this direction also there is room for progress — 
 and also for other methods producing the same effect 
 without violating the process patents which are now 
 reaping such harvests of profits for inventor and 
 manufacturers. 
 
 Calico-printers call for a cheaper material than 
 Senegal gum for filling the fabric before printing. 
 
 When an umbrella-covering woven in one piece, 
 as corsets are now produced, is put on the market 
 the inventor will find the market waiting for it. 
 
 And while the skilled inventor of textile machin- 
 ery is about it, why not produce a stocking all woven 
 in one piece, without any seam, and with double 
 toes and heels, and extra strong knees for little folks ? 
 
 Cloth wearing-apparel that will not shrink and 
 get out of shape when rained upon, and shoes that 
 may be wet without losing their shape and getting 
 stiff, would be good things if they were, in addition, 
 somewhat permeable to air, yet at the same time 
 moderately water-proof. 
 
 A process for cleaning cotton lace without wetting 
 it is called for by those interested. 
 
 A prize is offered for the best method of removing 
 dust from rooms where flax, hemp, and jute are 
 hackled. (See Chapter XXXIII.) 
 
 A machine for spinning asbestos better than those 
 now used would find no very extended sale, but 
 
Textile 131 
 
 would bring a high price. A Philadelphia carpet- 
 dealer once said to the author that spinning was 
 getting to be too much of a fine art, that the manu- 
 facturers of carpets could spin almost anything ex- 
 cept sand! For all that, asbestos spinning has not 
 reached a very high grade of perfection. 
 
 And when it comes to spinning moss fibers — 
 some of which have really very good qualities adapt- 
 ing them to textile purposes — there is even greater 
 lack of good machinery than for spinning asbestos. 
 The material is, to be sure, very varied, but if there 
 were good machines for spinning any one class of 
 moss, manufacturers would see to it that they got 
 sufficient quantities of that sort to enable them to 
 spin it regularly. 
 
 "Beaded" threads — that is, such as have at 
 regular distances beadlike enlargements somewhat 
 resembling beads strung on the thread — would be 
 welcomed by the manufacturers of fancy goods, 
 such as laces, curtains, fringes, etc. 
 
 If you can strengthen the sails of vessels by some 
 composition which will not stiffen the fabric you can 
 get rich. 
 
 The chemical philanthropist who produces a com- 
 pound which will fireproof and waterproof textile 
 fabrics at a low cost, and without changing their 
 appearance or feel, ought to be a millionaire before 
 his invention has been long on the market. If this 
 can be done without making the fabric air-proof as 
 well, so much the better. Garments which will shed 
 the rain, and boots which will exclude snow, while 
 
132 Hints to Inventors 
 
 permitting of the passage of air through their pores, 
 would be very desirable. 
 
 The author's namesake and relative, Robert — 
 afterwards Sir Robert, but nicknamed "Parsley- 
 leaf" — Peel, was the inventor of calico-printing; 
 and his grandfather, the inventor of the " discharge ' ' 
 process in that line, bought from Peel the patent 
 for the kingdom of Ireland, and founded the Irish 
 calico-printing industry in the neighborhood of Bel- 
 fast. The methods then employed were very prim- 
 itive: the blocks were about a foot square, and cut 
 by hand, and the printing was done by hand, regis- 
 ter being secured by pins. The invention of the 
 calico-printing roll, with the necessary machinery, 
 followed long after, and has all along been handi- 
 capped by the great expense of engraving the rolls. 
 A photo-engraving process for making the cylin- 
 drical printing-surfaces of zinc or copper would give 
 fresh impetus to the industry, and ought to bring 
 wealth to the inventor. 
 
 The first Napoleon said, in speaking of difficult 
 tasks, that nothing was impossible, except tying a 
 knot in the middle of a string both ends of which 
 were held fast. This is very much like the problem 
 which is set in making lace by machinery; but the 
 thing can be done, and has been done as far back 
 as 1878. Still, there is room for great improvement 
 as regards the size and cost of the necessary machin- 
 ery; and in this fine the consumption of the product 
 would be so great that the successful inventor of the 
 
Textile 133 
 
 lace-weaving loom should be able to realize well 
 from his inventive genius. 
 
 There are plenty of wire looms, such as they are, 
 that weave ordinary plain-mesh wire gauze and sieve 
 material; but as yet there is an opening for a loom 
 that will weave fencing and such material in fancy 
 patterns. 
 
 A great improvement in looms would be a device 
 by which the empty shuttles could be automatically 
 removed and replaced by full ones — without, of 
 course, stopping the loom for the change. The ca- 
 pacity of the loom would be increased, and consid- 
 erable labor saved. 
 
 A machine for making fish-nets seemed at one 
 time an absolute impossibility; but the problem has 
 been nearly solved by the lace-makers, and there 
 is no reason why fish-nets of mesh from half an inch 
 to four inches should not be made on one and the 
 same machine. How the knot is tied is a side issue ; 
 the main thing is that the meshes shall be of equal 
 size, and that the knot shall not slip. 
 
 Cloth-manufacturers express themselves as not 
 fully satisfied with the present machines for singe- 
 ing by means of gas-flames. 
 
Chapter XXV. 
 WRITING-APPLIANCES 
 
 Every year brings out a typewriting-machine — 
 and mostly, in nearly all respects a good one. But 
 there is always room at the top — and the top has 
 not yet been reached. The original typewriting- 
 machine — that of Dr. B. F. Palmer, the inventor 
 of the artificial arm and leg, samples of the wri- 
 ting of which machine are still preserved at the 
 Franklin Institute of Philadelphia — was about the 
 size of a so-called "cabinet organ," or let us say 
 of a small roll-top writing-desk; and it did what 
 then was considered wonderful work. Since then, 
 progress has been "upwards and onwards," as 
 Fourth-of-July orators say; so that the No. 5 or No. 
 6 of each manufacturer is as much better than the 
 No. 3 or No. 4 as these were than the No. 1 or No. 
 2 of the same make. But neither manufacturers 
 nor dealers nor customers are yet satisfied. They 
 demand a machine that shall have visible writing; 
 will write on letter-sheets, or freight manifests, or 
 post-cards, or envelopes; shall manifold well; shall 
 have two or three kinds of ribbon (as, for instance, 
 copiable and non-copiable, or red and black); shall 
 have more than two different line-spacings, and re- 
 placeable type, so as to be able to write with Polish 
 or Portuguese, German, or Esperanto, or any code 
 [ 134] 
 
Writing-Appliances 135 
 
 alphabet required, by simple change of the types 
 or wheels. This machine does not exist as yet. It 
 may never exist; but the probabilities are that it 
 will. When, in 1892 or so, the writer called for a 
 typewriting-machine that would write in books of 
 record, the idea was scoffed at; but two years after, 
 McCreary wrote him to come over to Jersey City 
 to see the new-born infant — which then wrote in 
 books, on books, on pocket-handkerchiefs, and even 
 on the walls and ceiling of the room. Now, the pur- 
 chaser can have his choice of half a dozen varieties 
 of machines that will write in books, make out bills, 
 etc. 
 
 For all that, the book- writing machine is not yet 
 just what is needed. Its work on narrow books 
 bound by the ordinary "case" plan, which do not 
 permit of being opened out very flat, is not what it 
 might be. And it is too big. 
 
 What would not the average daily newspaper 
 publisher and editor give for a small typewriting- 
 machine which the reporter could take with him 
 when in quest of news in that delightful class of 
 townlets denominated "nests"! There, no nimble- 
 fingered typist (good word, that; British) to take 
 down his "story;" the lead-pencil and the pad of 
 unsized paper must suffice — and here there are 
 chances for error, to say nothing of the greater time 
 required. The commercial traveler, also, would like 
 to have a small machine — not a toy — by means 
 of which he could write to his "house" those won- 
 derful romances about battle, murder, and sudden 
 
136 Hints to Inventors 
 
 death having prevented him from sending in orders 
 this time, but other circumstances rendering the 
 probable results of the next visit exactly epoch- 
 making. 
 
 It is too much to expect that the average music- 
 composer would ever learn to use a machine, when 
 (his eye, like that of the poet, " in fine frenzy rolling ' ') 
 he is evolving melodies to bring him fame and riches. 
 But there would be a good market for a machine by 
 which the choir-leader, or the band-master, or the 
 leader of the theatre orchestra, could have the various 
 "parts" written out rapidly and neatly on short 
 notice, by some one who was at once musician and 
 "operator." Such a machine would also enable the 
 cheap reproduction of amateur and fleeting compo- 
 sitions by the hektographic and mimeographic proc- 
 esses. 
 
 Electric drive for the typewriting-machine can 
 be accomplished. There are several operations 
 which could be electrically carried out — shifting 
 the carriage and throwing the roller by pressing a 
 button are perhaps the easiest. Before his death, 
 Dr. B. F. Palmer was at work on a tiny machine by 
 which the actual work of throwing the type-levers 
 was done by electricity; all the operator had to do 
 was to touch the key with a stylus. The keyboard 
 was about four inches square, or less. That was in 
 1895; but the electrically driven machine is as yet 
 hardly an every-day acquaintance. 
 
 With nearly all writing-machines there is a great 
 fault, — all the letters and signs that have but small 
 
Writing-Appliances 137 
 
 area get the same blow as the others, so that they 
 make a deeper impression and the imprint is unduly 
 full. Thus the period is usually driven clear through 
 the paper, while the m is printed more faintly than 
 the i. A variable touch would enable the operator 
 to give every character exactly the same impression, 
 and greatly increase the legibility and the beauty 
 of the writing. As it is now, one can tell a real type- 
 written letter from one that has been produced by 
 any of the now familiar processes by turning it over 
 and seeing if the periods stand out in relief like the 
 letters on printing for the blind. 
 
 A still further desirable feature would be a vari- 
 able feed for the carriage, by which the m and other 
 wide letters would get more room than the I and 
 other narrow ones, while the letters of medium 
 width, like the n, would get a medium amount of 
 feed. This problem has as yet baffled the inventive 
 skill of the veterans of the typewriter industry. 
 
 Typewriters make a dreadful noise. How can 
 this be deadened, so that every business office may 
 not resound with the unceasing rattle of the keys? 
 Any one of the big companies that sell such writing- 
 machines would gladly pay $50,000 cash for a sat- 
 isfactory solution of that puzzle. There are many 
 professional men who would gladly use the machine 
 for confidential and original work, but the " clapper, 
 clapper" distracts their ideas. 
 
 If the name of the duplicating-devices now on 
 the market is legion, there is at any rate an elegant 
 sufficiency of them, as regards quantity; and the pe 
 
138 Hints to Inventors 
 
 culiarity of them all is that whichever of them one 
 has, one wishes for the other. One kind yields copies 
 that gradually show oil through on the reverse side 
 of the paper; and if a hundred sheets are printed, 
 there must be a hundred sheets of blotting-paper, 
 between which they must be kept until they see fit 
 to dry. Another type leaves the sheets coated with 
 a thin film of glue size, which makes them curl as 
 if that were the chief object in using the apparatus. 
 And so on through the list. The ideal process must 
 be equally suited to pen and ink or typewriting- 
 machine; must not smear or curl the paper; and 
 must yield copies which are of equal strength from 
 the first to the last; and if possible it should be 
 adaptable to printing two or more colors at once. 
 The demands are exacting; are inventors afraid? 
 
 The hektograph ink in general use has the ag- 
 gravating peculiarity of being practically indelible 
 if it gets under the flnger-nails, but readily bleaches 
 out of documents printed therewith. Furthermore, 
 the color is characterless. Perhaps the aniline chem- 
 ists will produce something not quite so dependent 
 on glycerine for its consistency, and on the present 
 aniline compounds for its permanency. 
 
 The fountain-pen is responsible for rather more 
 profanity, for its weight, than any other object in 
 existence. But perhaps it would behave itself bet- 
 ter if it were treated better — as, for instance, by 
 being loaded with an ink that was jet black and 
 would not clog the fine passages. 
 
 Any government that has a postal department is 
 ready to hear from inventors who have an abso 
 
Writing-Appliances 139 
 
 lutely indelible canceling-ink for postage-stamps 
 that will fulfil the requirements of not drying up 
 hard on the pads, not clogging the letters of the 
 stamps by which it is applied, and not smearing 
 off from one letter to another. As it is now, most 
 of the canceling-ink in use can be removed by ordi- 
 nary soap and warm water. If the stamp is not 
 printed with a plate-ink that is also easily soluble 
 in warm soap-water, the opportunity for fraud is 
 great. But such plate-inks as are soluble in warm 
 soap-water do not yield sharp impressions; further, 
 are apt to bleach out by exposure to direct strong 
 sunlight. That is the status in this line; it remains 
 for those who think that they can deliver what is 
 called for to attempt it. "Faint heart ne'er won 
 fair lady." 
 
 It is thirteen years since I made my first call for 
 a good red pencil; and despite the thousands of in- 
 ventors who have read and acted on my list of sug- 
 gestions as to what to invent, and despite the fact 
 that my suggestions have brought out many im- 
 portant inventions — such as the typewriting-ma- 
 chine which would write in books, and the device 
 to enable a train to be braked from the switch-sta- 
 tion instead of only from the train itself (as for in- 
 stance, where it has passed a danger-signal) — the 
 good red pencil does not exist. Despite the fact 
 that in every double-ended red and blue pencil the 
 blue end, although used more than the red, lasts 
 longer, — so that the inferiority of the red end is 
 patent to every one who has used such pencils, — 
 the void remains unfilled. 
 
Chapter XXVI. 
 PRINTING 
 
 Perfection in typesetting-machines, which would 
 make books cheaper and lessen the cost of all printed 
 matter, is far from being reached. Machines which 
 will set up a page direct, and do the justifying at the 
 time the line is set up, ought to bring fame and for- 
 tune. 
 
 Half-tone printing needs the inventor's aid. As 
 it is now, ordinary presses for printing from type 
 forms must have engraved blocks, the printing- 
 surfaces of which are either type-high or below that, 
 and print from only those portions which are type- 
 high, losing the half-tone effect. 
 
 Are you able to invent an ink-distributing roller 
 for printing-presses, superior to those now employed ? 
 
 It might seem impossible to print several colors 
 at one impression, or at one passage through a 
 printing-press, but many things are being done now 
 which were at one time considered impossible, or 
 at least impracticable, and perhaps this will prove 
 to be one of those things. 
 
 Printing on sheet metal has not been so thoroughly 
 developed as it should be. There is plenty of room 
 here. The process should preferably be not litho- 
 graphic, but from relief surfaces. 
 
 Can you make printing-surfaces out of some ma- 
 [ 140] 
 
Printing 141 
 
 terial which shall be as light as celluloid, and as 
 easily molded, without being inflammable ? 
 
 There is room for some one to produce printing- 
 types having a hard face and a body which is not 
 so slippery that the letters will hardly stand on their 
 feet. 
 
 There is no cheap process for making borders and 
 tint-plates, for stocks and bonds, that would be im- 
 possible to imitate. There are many enterprises 
 that have but a few certificates of stock, where it 
 would not pay to have an expensive plate engraved 
 by the geometrical lathe, and book-printers (that 
 is, printers on relief presses) would welcome a 
 method of making them independent of the lithog- 
 raphers and steel-plate printers. 
 
 The black borders on mourning notices, writing- 
 paper, envelopes, cards, etc., are all put on by a 
 very tedious hand process. This delays the issue 
 and unduly increases the price. Who will be the 
 first in the field with something better ? 
 
 Alois Senef elder's invention of lithography, or 
 printing from stone, was based on the fact that you 
 cannot wet grease or grease water; but for many 
 decades it was practised with only stone as the print- 
 ing-medium. Later, zinc plates, and, still later, 
 sheet aluminium, were employed in carrying out 
 the same broad principle; there are, however, many 
 classes of work where metal is unsatisfactory. But 
 the high price and great weight of the true litho- 
 graphic limestone are a bar. The invention or dis- 
 covery of a new substance for this stone is a prob- 
 
142 Hints to Inventors 
 
 lem well worth the devotion of time and attention 
 thereto. 
 
 Lithographic printing-ink has the disadvantage 
 of not being as fully black as the ink used in plate- 
 printing, which is in itself very thick and black, and 
 being laid on in heavy masses, corresponding to the 
 depth of the incised lines in the steel or copper. 
 The production of a stone-printing ink that would 
 produce, when laid on in thin lines, the same jetty 
 effect that is observed in plate-printing would be a 
 benefit to lithographers who aim at high-grade work. 
 
 The progress of the idea of organization in all 
 business calls for keeping copies of many more doc- 
 uments and slips than were formerly used. This 
 means the use of either copying-ink or carbon-paper. 
 Where the entire document is newly and specially 
 prepared, it can be written on the machine; but 
 where there is a form to be filled out, it is usual to 
 copy in the press by the wet process. Generally the 
 ink employed in printing the forms is purple; some- 
 times it is green; neither of these colors is highly 
 desirable. But the copiable black printing-ink, 
 either for the lithographic press or the ordinary 
 "book" press using a relief printing-surface, does 
 not exist. It goes without saying that if it were in- 
 vented it would find no difficulty in being introduced. 
 
 If there is any one process which is more tedious 
 than another, it is plate-printing. There are power- 
 presses for using incised printing-surfaces, but those 
 of the roller type at once curl up the average thin 
 plate, while those of the stamp type soon totally 
 
Printing 143 
 
 destroy it. Both kinds do good work with printing- 
 surfaces specially prepared therefor; but these are 
 practically embossing-dies, and cost too much for 
 the average job. The remedy must be found in the 
 press, so as to enable the use thereon of plates al- 
 ready in use. 
 
 The art of rapid stereotyping for daily newspapers 
 is rather crude in its results, and although very rapid, 
 could stand considerable improvement without be- 
 coming too fine for rapid work. Every second saved 
 in the casting, and especially in the trimming of the 
 plate curved, is worth considerable money to the 
 proprietor of a daily newspaper having an energetic 
 rival. A number of years ago, the writer was very 
 handsomely paid for two weeks' work resulting in 
 a saving of seven seconds' time in the preparation of 
 the curved stereotype plates of the New York World. 
 This saving in time enabled that paper to be cried 
 on the street a few minutes before other papers re- 
 ceiving the same telegrams at the same time, and 
 having equally good composing-room facilities. The 
 idea was not patentable, and could not be kept se- 
 cret more than six months from the rival dailies; 
 but during that time it was a feather in the World's 
 cap. 
 
Chapter XXVII. 
 PHOTOGRAPHY 
 
 Photographers, especially those of the amateur 
 and dilettante classes — many of these latter have 
 more knowledge of the art than most professionals 
 — have long watched with interest the "telephot," 
 or long-distance objective, which enables photograph- 
 ing in comparatively large size and in great detail 
 small objects at a distance, or large ones which at 
 a very great distance subtend but a small angle. 
 
 In the best-known form — that of 1892 or so, as 
 proposed by Dallmeyer — it is in general principle 
 the optical arrangement of Galileo's telescope of 
 hundreds of years ago; or, to come down to modern 
 days, that of the common opera-glass. There is in 
 this latter a large concave or diverging lens of short 
 focus, and a so-called eye-piece having a short-focus 
 lens. If one turn one of the tubes of an opera-glass 
 wrong end to, and apply it so as to throw an image 
 on the ground glass of a camera, there will be ob- 
 tained a much larger image than could be got with 
 the same extension of the box, using the ordinary 
 objective. But the definition will be very bad. The 
 problem for the inventor of to-day is to produce 
 cheap telephot objectives that will give a large im- 
 age with sharp definition. The spherical aberra- 
 tion must be corrected for all focal lengths; which 
 [ 144 ] 
 
Photography 145 
 
 is where knowledge of the art comes in. By proper 
 attention to the adjustment for both positive and 
 negative spherical aberration, there can be attained 
 any desired amplification of the image. Should the 
 combination of lenses, or their adjustment, be such 
 as to produce a field which is convex towards the 
 lens (the reverse of the usual curvature), this can 
 be counteracted by using a small stop. 
 
 A peculiarity of the results obtained by the use of 
 such a lens is that by its use it is possible to get pho- 
 tographs that are practically in isometric projec- 
 tion — which would be of use to architects and to 
 military men. 
 
 The remarkable extension of the photographic 
 industry makes it desirable to decrease the cost of 
 grinding photographic lenses. Of course, the ma- 
 chines which would accomplish this result would 
 find purchasers among the manufacturers of spec- 
 tacles and opera-glasses as well. The requisites are 
 the production of perfect curves of exactly the char- 
 acter prescribed — for spectacles either spherical 
 or cylindrical. The same class of machine should 
 serve for both roughing and polishing ; and the result 
 should be approximately that necessary for tele- 
 scopic and microscopic work. The machine-made 
 lenses would then require none of the testing and 
 repolishing with the aid of the finger-tips necessary 
 for the highest grade of lenses. 
 
 The work of Meissenbach in Europe and Louis 
 E. Levy in America has wonderfully developed those 
 photo-engraving processes which enable our news- 
 
146 Hints to Inventors 
 
 papers and technical journals to be illustrated so 
 fully and so cheaply; while our permanent litera- 
 ture and the catalogues of manufacturing and com- 
 mercial firms show the benefits of the new art. But 
 there is much yet to be done. Blocking has not yet 
 been brought to the degree of cheapness and con- 
 venience which would please the photo-engravers; 
 for as it is, the nails work loose when the blocks are 
 dry, and often, as in the case of half-tone cuts, there 
 is absolutely no place to drive them, unless one 
 leaves therefor a margin, which increases the cost 
 of the block to the consumer and often takes up 
 more room than he had reckoned for. 
 
 The so-called "half-tone" process for reproducing 
 photographs and wash-drawings, as well as for de- 
 livering a printable block direct from a statue or 
 other picture, by direct photography (which is about 
 the same thing in effect as reproducing a photo- 
 graph), is really not a half-tone process at all, as 
 it yields by impression only absolutely black points 
 with absolutely white spaces between them. This 
 of course presumes that the ink is black and the 
 paper white. The process is limited by the capa- 
 bilities of the present presses for printing relief- 
 blocks, but those are the presses on which all cheap 
 printing must be done in these days; and the proc- 
 ess must be made to suit the presses long before 
 press-manufacturers are able to deliver machines 
 that will give real half-tones with existing blocks. 
 "Underlaying" and "overlaying," which were so 
 effective in the days of wood-engraving, and are so 
 
Photography 147 
 
 yet, where this is used, give wonderful mass effects; 
 however, they help but little with the so-called half- 
 tone blocks, because an effect cannot be produced 
 from a thing which does not exist, and the "lights" 
 on a half-tone block are represented by spaces only. 
 If there were really half depths, they could be made 
 to take less color than the parts of full height, and 
 more than those of full depth; but the aim in making 
 such blocks is to get all heights alike, or all depths 
 alike — which is after all the same thing. 
 
 The light-print has made itself by its own intrin- 
 sic and unmistakable merits indispensable to the 
 machine-builder and the architect and builder, 
 while the real-estate agent does not despise it. But 
 up to date the blue print is the favorite, not because 
 it is blue, and because its lines are white, but in 
 spite thereof. There are brown prints and blue 
 prints each with white lines and the other way about; 
 but as a rule they require two, if not three, baths, 
 are dirty to make, and require more time and skill 
 than are always available. 
 
 To make a photographic print with the sharpness 
 of the familiar blue print, and with the same quick- 
 ness and ease, but black instead of blue, has been 
 made the aim of photographers for some time. You 
 try. 
 
 If whoever invents a process for photographing 
 in colors reaps a reward commensurate with its im- 
 portance and the eagerness with which it will be 
 welcomed by the public, he will be a very rich man. 
 
 A good photographic bath for simultaneous de- 
 
148 Hints to Inventors 
 
 veloping and fixing positives has not yet been in- 
 vented. Such a bath would be desirable only on 
 condition that the pictures produced thereby should 
 be permanent and not bleach out, as is the case with 
 the majority of the compounds now offered for the 
 purpose. 
 
Chapter XXVIII. 
 
 AGRICULTURAL 
 
 Those who have seen the slow process by which 
 sugar-cane is cut — in Cuba by the ever handy ma- 
 chete, in India by the curved kukri sharpened on the 
 concave edge, and in every land where sugar-cane is 
 grown, by some particular form of knife, but always 
 by a knife, always by hand — will perhaps wonder 
 why there is no mowing-machine for cane. Prob- 
 ably it is because "what is everybody's business is 
 nobody's business." Be that as it may, there should 
 be a sugar-cane mowing-machine, and there is not. 
 It is not to be imagined that any one can get this 
 up who has not seen the cane growing, and been on 
 the spot at the season of cutting; but there are hun- 
 dreds of ingenious men among such as live in the 
 cane district, or get there from time to time, at the 
 proper season, and the reward of success would 
 make it worth while for them to go in vigorously 
 and attack the problem. 
 
 The districts in Germany, England, and Amer- 
 ica where hops are grown receive each year in the 
 picking-season an invasion of the unemployed from 
 other districts where there is little to do at that par- 
 ticular season. They are not always the very best 
 class of workmen, and the influx usually leaves be- 
 hind it a demoralizing effect; but often there is a 
 [ 149 ] 
 
150 Hints to Inventors 
 
 lack of even such labor, so that the condition of the 
 hop-grower is similar to that of the Scotchman who 
 said of the porridge that it was "cold, sour, burnt, 
 and gritty, and, damn it, there is n' t enough of it!" 
 
 There is more money in a good cotton-picker than 
 there has been in Eli Whitney's cotton-gin, and that 
 is saying a good deal. 
 
 Ties for cotton-bales cost too much money. Some 
 other way of fastening the bales is needed; and who- 
 ever gets it should name his own price for it. 
 
 Milking seems so easy! It is not. And there are 
 individuals who can milk only some particular cows. 
 The attempt to substitute machines for dairy-maids 
 and their trousered fellow workers has been a very 
 expensive failure for many inventors. But the prize 
 is worth the labor and the risk. One of the peculi- 
 arities of the task is that the cows which have been 
 hand-milked miss the person and simply refuse to 
 give down their milk to an air-pump or a suction- 
 hose. If, however, there were good machines, they 
 could be used at first only on animals which had 
 never been hand-milked; and if these latter objected 
 later to hand-milking, it would not make so much 
 difference. 
 
 The success of the incubator for prematurely born 
 and for other very weak infants shows what can be 
 done when a problem is scientifically attacked and 
 success is absolutely necessary. There are many 
 good incubators for poultry, but they all lack some- 
 thing, because they have not been properly ap- 
 proached, and have usually not been worked out 
 
Agricultural 151 
 
 by proper combinations of experienced poultry- 
 raisers and competent mechanics or scientists. The 
 best use to make of a scientist is to get him to pro- 
 duce something that it will not require another 
 scientist to use. Our Agricultural Department at 
 Washington is a good instance of the proper combi- 
 nation of practice with theory; and by " theory" I 
 do not by any means intend to convey the idea 
 usually falsely connected with properly directed, 
 consistent technical work, applied to suitable ma- 
 terial. 
 
 Millions of dollars are lost irrevocably every year 
 in America alone by the ravages of caterpillars, 
 moths, and other parasites. This is an example of 
 the strength of numbers. There is a limit to what 
 human hands can do; there is one to the number of 
 such pests that a ring of tar can stop. The writer 
 has seen in one German pine forest hundreds of 
 acres that were rendered absolutely worthless, ex- 
 cept perhaps for mine timbering and fire-wood, be- 
 cause for a space of about ten years a certain cater- 
 pillar had been quietly sapping the life of the trees. 
 Prevention would have saved them; cure there was 
 none. The same thing has happened in Massachu- 
 setts and in other parts of America. The country 
 would owe a debt of gratitude to him who would 
 invent or discover some way of combating these 
 pests, whether by a mixture to spray on the trees, a 
 compound to smear on the trunks, a solution with 
 which to saturate the earth, or another animal par- 
 asite to prey on the first. Only be it remembered 
 
152 Hints to Inventors 
 
 that the English sparrows that were imported to 
 kill off the caterpillars in Central Park, New York, 
 proved almost as big a nuisance as the caterpillars, 
 for they drove out all our native song-birds, and 
 eventually even the squirrels, that had so long made 
 the Park their home. 
 
 The writer recollects as a boy, living in the little 
 State of Delaware, one district where there were 
 225,000 peach-trees growing in one neighborhood. 
 Of these, 35,000 belonged to one family. There 
 are times when the trees overbear, and then the 
 peaches are not so good as usual; and by reason of 
 the greater quantity and inferior quality — to say 
 nothing of the lack of transportation facilities which 
 often manifests itself — the full or extra heavy crop 
 does not bring so much as the average crop. What 
 pays best of all is a third or a half crop. Now if 
 there could be a machine by which one third or one 
 half of the blossoms could be destroyed, it would 
 prevent the glut on the market, and the peach- 
 growers would be very willing to pay liberally there- 
 for. 
 
Chapter XXIX. 
 FLOUR-MILLING* 
 
 In wheat-milling there are two principal sources 
 of discoloration of the flour. First, there is a mechan- 
 ical discoloration, caused by the presence of minute 
 particles of crease-dust, "beard," and bran; and 
 second, a natural yellowish color of the starch in 
 the wheat-berry, aided by the yellow, fatty germ — 
 which latter, while very nourishing, or at least fat- 
 tening, has a tendency to cause souring if the flour 
 is not properly kept. For the first of these troubles 
 the remedy is purely mechanical, and must be ap- 
 plied early in the milling-processes: (1) more brush- 
 ing for the crease-dirt and the beard, and (2) better 
 handling of the bran — that is, it should be kept 
 flat and in as large flakes as possible. If properly 
 cleaned, it has about the same appearance on both 
 sides, instead of being white on the inside, as by 
 old process or "low" milling. Well-cleaned bran 
 has no more nourishment or flavor than so much 
 cocoanut fiber. For the yellowish color, unscrupu- 
 lous millers use alum and other "trade secrets." 
 Something better is needed. 
 
 The introduction of " roller" -milling does not 
 seem to have materially diminished the demand for 
 
 *See also the chapter "Inventions for which Prizes Are 
 Offered." 
 
 [153] 
 
154 Hints to Inventors 
 
 good millstones. As the quarries of La Ferte'-sous- 
 Jouarre and elsewhere are being exhausted, and as 
 in any case the natural stone comes in small pieces 
 which must be dressed to shape and hooped together 
 to form a millstone, the need of a substitute is appar- 
 ent. The new material must be hard enough to 
 stand wear — not merely as a matter of economy, 
 but to prevent particles of grit getting in the flour; 
 must be susceptible of being dressed into flats and 
 furrows, without spalling out; and must be slightly 
 porous, to give thousands of cutting -edges to catch 
 and sever the grain. The lighter in weight the bet- 
 ter; and all the pores must be approximately of the 
 same size. One of the great faults of the natural 
 stone is that it contains large cavities which have 
 to be filled with a cement — usually of magnesium 
 chloride, although unscrupulous millers often use 
 lead or its equivalent, which gets in the flour and 
 causes poisoning. 
 
 No one yet has been able to bale bran. Whoever 
 succeeds in doing with this material what is now 
 being done with cotton will find himself able to 
 dictate terms to capitalists. This is one of the things 
 that are called for — not seldom, but often ; not 
 faintly, but loudly; not by outsiders, but by those 
 who could use the machine. 
 
Chapter XXX. 
 HOUSEKEEPING APPLIANCES 
 
 Housekeepers often call for a preserving-can 
 of tinned iron or its equivalent, as glass, while having 
 the advantages of being easily cleaned for further 
 use, breaks too readily when subjected to the tem- 
 perature of the newly heated fruit, etc. ; and further, 
 the action of the light affects the color of some pre- 
 serves and the flavor of others. Glass is also rather 
 heavier than tin would be. The air-tight cover must 
 be in fact what its name implies. Such a can would 
 enable housewives in the country to preserve their 
 surplus fruit and send it to market, where glass 
 would cost too much for the necessary packing and 
 extra freight both ways. If I had another suggestion 
 to make it would be that the cans themselves should 
 be conical, so as to enable the "empties" to be 
 shipped in small space. 
 
 Is there only one firm in the entire world that can 
 make automatic spring rollers for window-shades ? 
 It would seem as though Spencer Hartshorne had 
 enjoyed this most profitable monopoly too long. 
 
 There are some circumstances under which the 
 Recording Angel (I have forgotten his name, but 
 that is immaterial) would excuse a few of what Mrs. 
 Malaprop or Mrs. Partington would call "cursory 
 remarks." ' One of these circumstances is where 
 [155] 
 
156 Hints to Inventors 
 
 carpet-nails come into question. Years ago we were 
 satisfied with carpet-tacks which were simply the 
 " common or garden " cut tack, supplied with a small 
 leather washer. And very good little fellows they 
 were too, if not exactly handsome. Nowadays we 
 have " carpet-nails, ' ' which possess all the bad qual- 
 ities of the average drafting-tack multiplied in ex- 
 act ration to the increased size. The weak point 
 in more senses than one is the place where the pin 
 joins the head. Here they either bend, or break off 
 short. He or she is lucky who can use one of these 
 abominations more than once. Here low price has 
 been made of undue importance; everything else 
 has been sacrificed to cheapness. Inventors to the 
 rescue. 
 
 The late J. Eastbourne Mitchell, so well and 
 favorably known in Philadelphia as "Grindstone 
 Mitchell," always asserted that there was nothing 
 like natural grindstone for sharpening carpet-tack 
 dies. It would appear that housekeepers thought 
 there was nothing but natural grindstone which 
 would sharpen table-knives. It remains for in- 
 ventors and manufacturers of emery-wheel grinding 
 machines (which does not mean machines for grind- 
 ing emery-wheels, Mr. Hypercritic) to produce a 
 light, high-speed machine for household use, so 
 simple that the average servant could not get it out 
 of order, and so arranged that it would give the 
 knives the proper edge, whether or not the workman 
 or workwoman was "skilled in the art," as the pat- 
 ent applications read. The old-fashioned grindstone 
 
Housekeeping Appliances 157 
 
 is too slow and rough, but there is little better of- 
 fered for domestic purposes. 
 
 Some housekeepers, and many, many keepers of 
 hotels and restaurants and the like, call for a simple, 
 light, bread-cutting machine, on which the thick- 
 ness of the cut might be regulated, and the knife of 
 which could readily be taken out and sharpened on 
 an ordinary household wheel. This last clause bars 
 out all knives with curved blades, intended to give 
 a draw-cut. The draw-cut is an essential, but manu- 
 facturers of paper-cutting machines find that straight 
 blades are exactly right for their difficult work, and 
 this should be the case with bread, also. 
 
 There are in the household many little losses 
 which evoke anger; one of them is the breakage of 
 eggs. A simple egg-chest is one of the things which 
 are often enough called for to make it worth the 
 inventor's while (the author does not know what a 
 "while" is, but that is the usual phrase) to get up, 
 and place on the market. 
 
 Since the author called for a device by which 
 eggs could be cooked on the breakfast-table any 
 desired length of time and the lamp then automat- 
 ically extinguished, a German dealer in household 
 articles informs him that he has one in preparation; 
 but from his description the author is awaiting at 
 this writing a complicated and expensive arrange- 
 ment. There is room for half a dozen ways of ac- 
 complishing the result, which of itself is unpatent- 
 able. 
 
 There are many housewives of the old school who 
 
158 Hints to Inventors 
 
 lament the disappearance of the copper kitchen 
 utensils of their youth, such as are still seen in French 
 kitchens and on board ship. While admitting that 
 they are picturesque, that liquid will boil in them 
 more rapidly than in enamelled ware, and that 
 they have the good quality that one always knows 
 whether or not they are spotlessly clean, the author 
 has had the bad luck to have been poisoned in Ger- 
 many by eating marmalade cooked in one of the 
 much lauded " coppers," and has no desire to repeat 
 the experience. He would therefore suggest as an 
 alternative a cheaply made utensil of sheet steel, 
 plated with copper and then tinned inside — and 
 perhaps also outside. The invention would consist 
 in the process of producing these cheaply. 
 
 Machines for sewing on buttons seem to be just 
 a little beyond our reach so far. When they come, 
 if they do the work properly, rapidly, and cheaply, 
 they should be a pecuniary success. 
 
 It is about time now for some one to get ready to 
 produce a household filter for drinking-water — 
 something that will not clog up, that is easily cleansed 
 or renewed, and will have capacity for rapid passage 
 of the water. 
 
 Another thing that is much wanted in the world 
 is a floor-scrubbing machine. Invent one! If you 
 do not, somebody else surely will, and then you will 
 be sorry. Think what a boon such a contrivance 
 would be to overworked housewives, and give your 
 brain an extra hard day's work. The machine must 
 use soap and water or its equivalent and wipe the 
 
Housekeeping Appliances 159 
 
 floor dry after cleaning it; furthermore, the dirty 
 water must not be returned to the receptacle for 
 clean. 
 
 How about a substitute for carpet — just a floor- 
 covering that will serve the same purpose at less 
 cost? You can be a multi-millionaire before the 
 year is out if you can solve that little problem. 
 Look what the Linoleum people have made and 
 still are making! 
 
 Sewing-machine manufacturers and housewives 
 would unite in welcoming an invention by means of 
 which the ordinary household sewing-machine would 
 be able to use thread from the wooden spools on 
 which it is bought in the stores, instead of having 
 to be respooled on small steel bobbins — a process 
 that consumes too much time, especially in " straight 
 seaming" at high speed, where the bobbin -wind- 
 ing takes comparatively too much time. 
 
 Perhaps you can contrive a simple and inexpen- 
 sive tool that will cut ice without wasting it, taking 
 the place of the wretched and extravagant ice-pick 
 now in use. Why not try, any way ? There should 
 be about it somewhere, one would think, the prin- 
 ciple of the saw; and it must be made with due ref- 
 erence to the fact that while ice is easily split in a 
 direction at right angles to the upper surface of the 
 cake as it lies on the water on which it is frozen, it 
 is extremely difficult to split in any other direction. 
 In this particular it is to be treated like a block of 
 "end wood." 
 
 After all, it is not always so very hard to get rich. 
 
160 Hints to Inventors 
 
 Fortunes offer themselves on every hand as rewards 
 for a little ingenuity. For example, a machine is 
 wanted that will open oysters. If you can make one 
 that will do the work satisfactorily, it will render 
 you independent for life. 
 
 Most people, especially women, cannot sharpen 
 their own knives. They need some little machine 
 that will enable them to get over the difficulty. Why 
 not make one, and patent it? First, however, fig- 
 ure out what is needed and what is not needed ; then 
 inquire whai has been offered on the market to sup- 
 ply the need; then, having analyzed these and found 
 out their good and their weak points, work out your 
 own ideas so as to "cover the ground." 
 
Chapter XXXI. 
 IN MUSICAL LINES 
 
 Even musicians, who resent the idea of having 
 anything in common with "practical" people, and 
 condemn all piano-playing apparatus (unless paid 
 large sums to sign laudatory testimonials about 
 them), have their wishes which they desire to make 
 known to the inventive class. They want, in the 
 first place, a machine which will give the fingers a 
 limbering-up, such as would otherwise have to be 
 accomplished by practising for four or five times as 
 long. This would be a sort of Swedish movement 
 exercise, accomplishing the desired flexion of the 
 muscles and increased circulation of the blood, with 
 consequent increase in the muscular strength, which 
 would otherwise call for considerable expenditure 
 of nerve force. Their neighbors would no doubt 
 welcome anything that would give relief from so 
 much practising. It should not, however, be one 
 that would be likely to ruin the hand, as was un- 
 fortunately the case with one invented by Schumann 
 in his early days, which by crippling his right hand 
 prevented his ever playing again. 
 
 A second invention which piano-players and other 
 
 performers call for is a device for turning over the 
 
 pages of sheet music. Some have been produced, 
 
 but they are not capable of handling sheets of differ- 
 
 [161] 
 
16£ Hints to Inventors 
 
 erent thicknesses and qualities of paper without 
 special adjustment for each sort; and some of them 
 demanded more work to make them turn the page 
 than would have been necessary to do the work of 
 page-turning itself. Again, some of them would not 
 readily stand on many makes of piano; and as there 
 is such a variety of racks, this would cut them out 
 from general use. 
 
 Musical composers have long sought an apparatus 
 which would register their impromptu compositions 
 or their tentative studies — not as a phonograph or 
 gramophone would do it, but in characters which 
 could be transcribed into the ordinary notation, if 
 not in the regular notes familiar to every one. There 
 is many a musical gem lost to the world because the 
 composer who had evolved it, by a happy touch, 
 could not later remember just what the combina- 
 tion that produced the admired result was. 
 
 There are many more persons who love music, 
 and understand it, but who cannot play any instru- 
 ment, than there are good performers. (I might go 
 further and say that there are many who play con- 
 stantly and play so badly, without knowing it, that 
 their playing should be forbidden by municipal 
 ordinance.) The great majority of really musical 
 non-performers would be blessed by a half-automatic 
 attachment to the piano, by which the merely tech- 
 nical part of playing could be attended to by the 
 attachment, while the " semi -performer " could give 
 such expression or interpretation as seemed to him 
 best. For Germany and Austria it would be well to 
 
In Musical Lines 163 
 
 have such an instrument or attachment for the zither, 
 as well as one for the pianoforte. 
 
 In the many kinds of automatic musical instru- 
 ments with Greek names there is one nuisance in 
 common: the difficulty of changing the perforated 
 plates or strips which determine the air to be per- 
 formed. They are frequently damaged in putting 
 them in or taking them out or while they are put 
 away. It would be very much better if they could 
 be kept always in the instrument and changed in 
 the same manner as the shift of a barrel-organ cyl- 
 inder is accomplished — by merely pushing in or 
 pulling out a stop. 
 
Chapter XXXII. 
 MISCELLANEOUS 
 
 Most of the fire-hose made of seamless canvas 
 has the great fault that if lined with India rubber 
 the inner portion does not remain fast on the can- 
 vas, but comes loose in blisters, which diminishes 
 the capacity of the hose. The writer has seen the 
 entire hose stopped at a fire by a long section of 
 lining getting loose and completely clogging the pas- 
 sage of water. 
 
 Four-ply hose, on the contrary, made of alternate 
 layers of muslin and rubber, or rather of four plies 
 of muslin coated with rubber, has either one fault or 
 another, both producing the same evil result. Al- 
 most without exception, such "plied" hose either 
 expands or contracts in length under the internal 
 pressure of the water. Usually it contracts. If it 
 shortens when pressure is applied, it has a tendency 
 to pull from the ladder the fireman who has carried 
 the line up and then calls for water. If he hooks it 
 to the ladder, there is danger of pulling this with it. 
 If, on the contrary, it lengthens under pressure, 
 then when the water is purposely shut off, or in case 
 a section bursts, the shortening takes place, with 
 the same dangerous result. There is a chance for 
 some one to get up a hose which will neither con- 
 tract nor expand in length when under pressure; 
 [ 164] 
 
Miscellaneous 165 
 
 also to produce a seamless tubular canvas hose that 
 will be water-tight under four hundred pounds pres- 
 sure to the square inch, and not be liable to come 
 apart in service. 
 
 The street letter-box locks in most countries can 
 be very readily picked. A much better arrange- 
 ment than the present key-lock would be a combina- 
 tion time and key lock, which could be adjusted by 
 the collector, so that it could be opened even by the 
 proper key only at such time as was predetermined 
 at the last collection. This would prevent the use 
 of false keys or of pick-locks at such times as the 
 boxes are not under the observation of passers-by; 
 and would even prevent thieves in carriers' uniform 
 and provided with false keys relieving the boxes of 
 their contents shortly before the regular collection- 
 time. 
 
 The ordinary lettering-brush used in marking 
 boxes and bales, without the use of a stencil, does not 
 give so good results as might be desired, as much 
 time is lost in dipping it in the paint or ink. If a 
 fountain-pen is good for writing on paper, why 
 would not a fountain-brush be good for this letter- 
 ing-work, which, after all, is only writing on a large 
 scale ? 
 
 Much is said concerning the dangers of automo- 
 bile sport, but when one dips into statistics and 
 looks under the head of "Runaway Horses," one 
 is confronted by the fact that they are even a greater 
 source of accident to life and limb than are the au- 
 tomobiles. A method of preventing such accidents, 
 
166 Hints to Inventors 
 
 either to the occupants of the vehicle or to those in 
 the street or road, has been long called for; and there 
 are many patents on the subject; but as yet there 
 seems to be no abatement of the evil. Electricity 
 and all sorts of things have been tried, but most of 
 the devices have been either too complicated or sim- 
 ply ineffective. The writer, having been very badly 
 smashed up in such an accident, can see just where 
 the invention would be useful. Accident-insurance 
 companies would be apt to recommend a good one 
 to their policy-holders. 
 
 Is flexible glass too chimerical for American in- 
 ventive genius ? 
 
 The practical utilization of peat has only begun. 
 This material, so universally distributed all over 
 the world, has a great future. The principal diffi- 
 culty in making use of it is in getting rid of the im- 
 mense quantity of water which it contains, and ma- 
 king it into blocks or plates without having to use 
 either very heavy and costly machinery, or expen- 
 sive "bond," or both. 
 
 Plants for the carbonization of peat have been 
 called for again and agian, but are not offered for 
 sale. Two distinct sizes are demanded: one with 
 an immense capacity, for very large plants, and 
 another quite small one for what might almost be 
 called domestic use. A medium size would hardly 
 be called for until the industry got fairly on its 
 feet. 
 
 Every year millions of tons of sawdust go to waste. 
 In some of our saw-mill districts "crematories" are 
 
Miscellaneous 167 
 
 built, in which to burn it, as letting it go into the 
 streams is apt to kill fish and clog the turbines. There 
 is material and to spare; what can inventors make 
 thereof? Briket fuel, flat slabs for flooring, and 
 blocks for street-paving — all these would use up 
 a material which now goes to waste; but there is 
 needed a suitable "bond" and proper machinery 
 to make the thing commercially possible. 
 
 The biograph or bioscope apparatus now before 
 the public seem to have in common one great fault, 
 — that they give trembling pictures. The reason for 
 this is that the pictures are taken on a constantly 
 moving strip of gelatine, while the exposures are 
 consecutive although their duration is but short. 
 The result is that all the pictures are slightly oval, 
 and that they do not join on the screen. If the 
 camera apparatus were to make allowance for the 
 opening and closing of the shutter by halting the 
 film when the shutter was open, and only then, this 
 trembling would in great part disappear. 
 
 There are folding opera-glasses which fold all 
 right enough, but are in the habit of shutting up at 
 the most interesting moment of their use; further, 
 they are extremely inconvenient to hold. Who will 
 make better ones ? 
 
 There is no good instrument for measuring the 
 velocity of the wind or of a current of air. A good 
 one could be used not only in scientific observations, 
 but in the industrial arts. 
 
 The pyrometers which are on the market give at 
 best but crude guesses at the temperatures which 
 
168 Hints to Inventors 
 
 they are supposed to indicate. A good one would 
 pay, if simple and reliable. 
 
 Inventors of a surgical turn of mind might find 
 it profitable to devote their attention to producing a 
 good appliance for holding the patella or knee-cap 
 when it is fractured. At present it is practically 
 impossible in nearly every case. 
 
 There are on the market water-tight watch-cases, 
 but they are screwed together, and a very slight 
 injury makes it impossible to unscrew them; while 
 sometimes, even under normal conditions, opening 
 them is difficult. An air-tight case would exclude 
 both moisture and the fine dust that comes from 
 the cloth of the pocket, and from the surround- 
 ing air. Such a case would prolong the fife of a 
 watch and increase the accuracy of its time-keeping. 
 
 There are few toothbrushes, even of the best sort, 
 in which the bristles are so well fastened in that after 
 a brush has been in use for some little time they will 
 not pull out in use — which is not only expensive, 
 but highly unpleasant, and has sometimes led to 
 choking. 
 
 Barbers call for apparatus for disinfecting razors 
 at the time of stropping them. The entire range of 
 barber's implements should have cheap and effect- 
 ive means of disinfection. Even the reputed richest 
 man in the world has been the victim of a skin- 
 disease, caught at a barber's, and has thereby lost 
 all his hair and beard. 
 
 A foaming beverage free from alcohol, and having 
 a pleasant taste and no cathartic or other undesir- 
 
Miscellaneous 169 
 
 able effect on the digestive tract, so that it could 
 take the place of beer, would sell well. Even if it 
 contained as high as one per cent of alcohol, it would 
 not matter much, as no one could hold enough thereof 
 to become intoxicated thereby. 
 
 Bones, intestines, and other animal offal could be 
 very well used as food for dogs, if some one would 
 invent a sort of meat-cake made therefrom (like the 
 present so well-known dog-biscuit) which would 
 keep in any climate and temperature. 
 
 A process for removing the deposit from the bot- 
 toms of old port-wine bottles would be well received. 
 
 A fortune awaits the man who will invent a sat- 
 isfactory hairpin — a pin, that is to say, which will 
 really hold the hair in place and not "come loose." 
 Hundreds of patents have been granted for as many 
 different patterns of hairpins, but not one of them 
 meets this requirement. The weekly consumption 
 of hairpins reaches far into the millions. The new 
 invention must go in easily, only come out when the 
 wearer desires, and must not split or tear the hair. 
 
 There are on the market two kinds of self -thread- 
 ing needles, — that is, such as do not require the end 
 of the thread to be carefully steered through the eye, 
 — but neither of them can be used with silk. So 
 those who know say. 
 
 Thousands and thousands of smokers have 
 longed for a convenient cigar-lighter to dispense 
 with matches. "The last match always goes out" 
 when one is fishing from a boat, or is in some other 
 situation where more matches cannot be obtained. 
 
170 Hints to Inventors 
 
 How many million cigar-holders are used each 
 year ? And how many hold the cigar firmly ? This 
 is principally because there are so many different 
 forms and sizes of cigar-tips; but holding these is 
 just the problem. 
 
 An air-tight metal capsule covering for beer and 
 mineral-water bottles would be readily made profit- 
 able, if light, cheap, and reliable. 
 
 Umbrella-makers tell the author that they would 
 like to hear of a good process by which umbrella- 
 sticks with right-angled "grips" could be made, by 
 bending or otherwise, more cheaply than at present, 
 and without splitting the wood by reason of the 
 different curvature of the inner and the outer sides 
 of the bend. 
 
 The development of the ordinary skate — since, let 
 us say, 1850 — has not been so rapid as would have 
 been the case if inventors had had their attention 
 attracted thereto. We have, however, at any rate got 
 beyond the stage when we believed that it was ab- 
 solutely necessary for the runner to be grooved 
 (many a time has the author stayed off the ice be- 
 cause his skates were not "guttered"), and the time 
 is long since past when there was a wooden sole 
 with a screw which was driven into the boot-heel, 
 or a stud fitting in a plate in the latter. With these 
 times are gone the days of feet so tightly strapped 
 up that they become absolutely insensible. But still, 
 for all the conveniences in clamping the modern 
 steel-soled skate to the boot, there is much left for 
 the inventor to do to accommodate the skate to 
 
Miscellaneous 171 
 
 different heights and shapes of boot-heels, and to 
 perfect other details. 
 
 Cremation would be more rapidly introduced if 
 there were a little more science and a little more 
 common sense in the furnaces which have been 
 proposed and tried for effecting it. A man may be 
 willing to risk spoiling the making of a batch of steel 
 by an imperfectly made furnace, but no one wishes 
 to try — even upon his mother-in-law — an imper- 
 fectly working crematory. 
 
 The man or the woman who will get up something 
 better than the present high hat in the way of dress 
 attire for the sterner sex will deserve well of his or 
 her countrymen. The civilized world — or at least 
 the European and North American parts thereof — 
 is under the bondage of the high silk hat. It is hid- 
 eous, uncomfortable, and dear; and requires con- 
 stant ironing and daily or even more frequent " slick- 
 ing." It is perhaps too much to expect that a sub- 
 stitute will be produced which will drive it out to 
 follow the crinoline. 
 
 Our modern foot-gear is highly injurious to the 
 feet, because it is un ventilated ; and until this venti- 
 lation is accomplished our feet will be tender. The 
 use of india-rubber overshoes increases the evil. 
 
 To get down to an article for every-day use by 
 every one — there is no good newspaper-holder. 
 There is a great variety, but not an "elegant suffi- 
 ciency," because they do not suffice. As a proof of 
 this statement, try to eat your breakfast and read 
 your newspaper at the same time. And then essay 
 
172 Hints to Inventors 
 
 taking the paper from the "file" and replacing it. 
 Those holders that can be held are unpracticable 
 as regards ease and security of filling; and the ones 
 that can be readily filled, and which stay filled, can- 
 not be held in one hand at the breakfast-table. 
 
 Any one who has ever lamented the miserable 
 method of case-binding in vogue will confirm the 
 statement that there is room for a better system, 
 which will permit books to be opened out flat like an 
 Oxford Bible and allow the entire page to be laid 
 open to view. It must, of course, be as cheap as 
 the present system. 
 
 An envelope that cannot be opened without de- 
 tection is yet to be invented. Can you not solve the 
 problem ? As Colonel Sellers used to say, " There 's 
 milhons in it." 
 
 Speaking of envelopes, what is the matter with 
 devising one that is suitable for carrying small arti- 
 cles through the mails ? Nothing really good of the 
 kind exists at present. Will you not step into the 
 breach and, while covering yourself with glory, fill 
 your pockets with money? First, however, inquire 
 what is already on the market, and what the post- 
 office authorities specify as prerequisites. 
 
 All the foregoing are possible things to produce. 
 There are many things for which we would all de- 
 voutly pray if we thought they could be produced; 
 as, for instance, an automatic jainitor who would 
 not steal coal and would not read our papers in the 
 morning before sending them up; a self-acting me- 
 chanical barber who would not eat onions or garlic 
 
Miscellaneous 173 
 
 and would not smoke bad cigars nor tell you how 
 sick he was the day before. These are consumma- 
 tions devoutly to be wished, but there is little or no 
 hope that they will ever appear. 
 
 A sensitive cornet which would blow the player so 
 full of flour, if he played falsely, that he could not 
 play again for a week would be a great boon to a 
 suffering community; as would a machine which 
 would pick the bones out of shad. 
 
 I have enumerated many lines which offer sub- 
 stantial reward for practical inventive skill ; but have 
 not named them all, nor nearly all. Space would not 
 permit this. Those who are interested in such sub- 
 jects and are on the alert for "tips" concerning 
 good directions in which to apply their talents should 
 keep their eyes and ears open and their mouths shut. 
 
Chapter XXXIII. 
 
 INVENTIONS FOR WHICH PRIZES 
 ARE OFFERED 
 
 The management of the Milan International Ex- 
 position was empowered by the "Associazione dcgli 
 Industriali d 'Italia per pre venire gle Infortuni del 
 Lavoro" to offer the following: 
 
 (1) A gold medal and 8,000 lire (about $1,600) 
 for a new system of preventing the dangers arising 
 from contact of high-tension with low-tension elec- 
 tric conductors, as in "step-down" transformers 
 of the alternate current. 
 
 (2) A gold medal and 1,000 lire (say $200) for a 
 crane or other hoisting-device with a simple and 
 practical arrangement by which to prevent the load 
 from running down the crank, if the latter be left 
 free, as in lowering. 
 
 (3) A gold medal and 500 lire (say $100) for a 
 simple, strong, and reliable safety device to hold a 
 mine-wagon on a slope, if the cable breaks. 
 
 (4) A gold medal for an invention for exhausting 
 and collecting the dust arising from sorting and cut- 
 ting up rags, as in paper-mills. The device must 
 not create a draft. 
 
 (5) A gold medal for a device which will remove 
 and collect the dust arising from carding flax, hemp, 
 jute, etc. 
 
 [174] 
 
Prizes for Inventions 175 
 
 (6) A gold medal for an arrangement by which 
 to prevent the spread of dust in rooms where lime 
 and cement are handled. 
 
 The address of the Secretary of the society above 
 named is: Foro Bonaparte, 61, Milano, Italy. 
 
 The Paris daily journal Le Matin offered a prize 
 of 10,000 francs (about $2,000) for a method of de- 
 stroying flies, which are said to be the means of 
 propagating cholera. [This may be the fact, but 
 the author thinks that flies do a great deal of good 
 by consuming decaying and other matter which 
 might otherwise cause disease; and that the best 
 way to avoid cholera is to keep everything abso- 
 lutely clean, and to eat or drink nothing uncooked.] 
 
 A prize of 100,000 francs (about $20,000) was 
 offered by the heirs of the Washington patent lawyer 
 Pollak, who was lost on the Bourgogne for the fol- 
 lowing inventions: 
 
 For preventing collisions at sea; for saving the 
 ship, in case a collision occurs; for saving the pas- 
 sengers, in case the ship goes down. 
 
 Prizes of from 2,000 up to 5,000 marks are offered 
 by the German War Department for the best de- 
 sign for portable field-kitchens. These must be 
 light, yet strongly built, arranged to be drawn, with 
 their entire contents, by one horse, on soft ground, 
 and must be able to follow the troops over uneven 
 country. The gage is fixed at 1,553 millimeters, 
 or 61 inches; the kettle must hold 150 liters, or prac- 
 tically 40 United States gallons. The cooking- 
 arrangements must be such that the kitchen can be 
 
176 Hints to Inventors 
 
 used for preparing meals while in movement, so 
 that a halt for this purpose need not be necessary. 
 The fireplace must be suited to all kinds of fuel in- 
 differently — wood, coal, peat, straw, etc. Designs 
 in competition are to be sent in to the Train Depot 
 of the Garde Korps, Tempelhof, Berlin, by the 
 fifteenth of February, 1906. 
 
 The German Society of Railway Managers (Ve- 
 rein Deutscher Eisenbahnverwaltungen) offers every 
 four years prizes of 30,000 marks (about $7,150) 
 for important inventions and improvements in rail- 
 way lines. These prizes are as follows: 
 
 (1) For improvements and inventions in the fine 
 of constructive and mechanical devices for railways 
 and their operation, a first prize of 7,500 marks, a 
 second of 3,000, and a third of 1,500. 
 
 (2) For inventions and improvements concern- 
 ing the construction and operation of the engines 
 and rolling-stock, prizes of 7,500, 3,000, and 1,500 
 marks respectively. 
 
 (3) For inventions and improvements concern- 
 ing railway management, direction, and statistics; 
 and 
 
 (4) For remarkable literary work concerning rail- 
 ways — for 3 and 4 together, one first prize of 3,000 
 marks and two of 1,500 each. 
 
 Without limiting the competition to other rail- 
 way topics, and without binding the Committee of 
 Awards, the following subjects are suggested by the 
 society as well worth working up: 
 
 (a) Mechanical locomotive-stoking. 
 
Prizes for Inventions 177 
 
 (b) Improvements in steam-heating trains, par- 
 ticularly long ones. 
 
 (c) Air-brake hose-couplings, by which the shut- 
 off cocks could be dispensed with without affecting 
 the automatic action of the brakes. 
 
 (d) Devices for facilitating communication be- 
 tween the members of the train crew, especially 
 for long passenger and freight trains, and for freight 
 trains without continuous brakes; also in tunnels. 
 
 (e) A critical discussion of the question of motor- 
 cars, and that of hauling light trains by these or by 
 locomotives, from the technical and the financial 
 standpoints. 
 
 (/) Simplification of the operations in distributing 
 the traffic and charging up proportional freight 
 rates. 
 
 The German Society of Mechanical Engineers 
 (Verein Deutscher Maschineningenieure ; not to 
 be confused with the Verein Deutscher Ingenieure) 
 has offered prizes for studies concerning increase in 
 the capacity of the Berlin elevated roads and con- 
 nections (Berliner Stadtund Ringbahn). 
 
 (1) As to whether the capacity of the road and 
 its connections could be increased by using two- 
 story cars approached from two-story platforms. 
 The trains are to be electrically driven by single- 
 phase alternating currents; the studies should em- 
 brace the electric appliances in and on the cars and 
 the trolleys or other current-collecting devices. 
 
 (2) The track must be usable as before by the 
 present locomotive-drawn trains. 
 
178 Hints to Inventors 
 
 (3) The passengers must be protected from in- 
 jury, and the upper doors closed when the train is 
 not at the platforms; starting must be impossible 
 until all doors are bolted. [Whether this feature is 
 desirable, without means of leaving the train in case 
 of a breakdown or of getting out of the cars in case 
 of derailment or fire, is, in the author's mind, a 
 question; but that is what the society calls for.] 
 
 (4) There must be no confusion in seating, and 
 no counter-currents of passengers in getting in and 
 out. [As the platforms are sometimes on one side 
 of the track, sometimes on the other, as with the 
 Paris Underground Railway, the author thinks that 
 this problem is hardly capable of solution without 
 the aid of a sergeant and two corporals in each car, 
 and placing the entire population, including stran- 
 gers, under martial law, or at least military regula- 
 tions.] 
 
 (5) Passengers must be protected against being 
 crowded out of the cars, and stepping between car 
 and platform or between two cars. 
 
 (6) The traffic is preferably to be directed to the 
 lower story, hence the third-class compartments 
 should be below. The question of cross-seats, etc., 
 is to be considered. 
 
 (7) The matter of hinged doors and sliding doors 
 is also to be considered. 
 
 (8) Swinging of the cars is to be reduced perhaps 
 by lowering the floor of the under story. The ques- 
 tion of sliding axles or pivoted trucks is to be weighed. 
 American couplings are to be used. The heating 
 
Prizes for Inventions 179 
 
 and lighting are to be electric; the brake, pneu- 
 matic. 
 
 (9) Papers on the subject are to be illustrated by 
 sketches. 
 
 Details can be had by addressing the Society 
 Verein Deutscher Maschineningenieure in Berlin, 
 
Chapter XXXIV. 
 PERFECTING AND DEVELOPING 
 
 A few disinterested words about perfecting and 
 developing inventions may not come amiss. 
 
 Perfect every invention before you try to patent 
 it. By "perfect" I mean get it into practicable 
 shape. Then you will not have to be constantly 
 taking out new patents at the same expense as the 
 original one; will arrive at a working result just as 
 quickly; and will not be giving others the hint to 
 work up the same line with yourself. 
 
 Patent your invention before putting it into prac- 
 tical operation on a large scale. It is all very well to 
 have right on your side, but an interference suit is a 
 very unpleasant thing to have. Where possible, see 
 that your process or machine is all right in every way 
 before you make your application for protection 
 thereon. It may turn out not worth protecting ; or it 
 may be so valuable that it would be very bad pol- 
 icy to set any one else on the same hunt. 
 
 Put your invention in practice before you try to 
 sell it. To some this may seem very like saying, 
 "Don't get in the water until you can swim;" but 
 what I mean is, make no serious attempts to inter- 
 est capital for working your invention on a large 
 scale before you have something tangible and prac- 
 tical to offer, It is all very well to interest some one 
 [ 180] 
 
Perfecting and Developing 181 
 
 with you in the preliminaries to help you make your 
 first instrument, and to get your invention patented; 
 but when you come down to asking for money by 
 the hundred thousand, or even by the ten thousand 
 dollars, you had better have a better bait than an 
 undeveloped invention. 
 
 In this connection let me caution you against 
 showing imperfect models and sketches. Whenever 
 you have anything to show to anybody else, any- 
 thing to sell, see that you have a good sample, or a 
 good bait. A model or a drawing for which you 
 have to apologize, or which will fail you just when 
 you want it to appear at its best, will not even draw 
 money well for prekminaries; and as a bait for large 
 capitalists, it is like a piece of watermelon-rind for 
 trout. 
 
 Do not expect too much. It sounds well to say, 
 "The higher you aim the further you shoot;" but 
 there are some distances at which no one could hit 
 anything. You might aim straight up in the air and 
 not be able to hit the moon. Don't expect that mil- 
 lionaires are going to come around to your house 
 evenings to interest themselves in your invention; 
 or that they will drop their business and give you 
 hour after hour, much less day after day, looking 
 up what you have. Millionaires do not make their 
 millions that way. If you get a presentable show- 
 ing ready, understand it well, and are able to explain 
 it promptly and without egotism or braggadocio, 
 and to respond to all questions which may be put 
 on the subject, you need have little trouble in get- 
 
182 Hints to Inventors 
 
 ting a large enough audience — always supposing 
 that your idea is in a line where invention is needed, 
 and that all other conditions are favorable. You 
 must not expect patents to be any more salable, or 
 salable under more adverse conditions, than mer- 
 chandise. 
 
 Don't think that the whole country is lying awake 
 of nights in the vain hope of having just such an 
 invention as you have produced — or think that you 
 have produced. The country at large, and manu- 
 facturers and others in particular, will probably 
 welcome your invention as soon as you have shown 
 (1) that it is an invention, (2) that it is in a line in 
 which invention is needed, and (3) that it will work. 
 
 In getting it patented, avoid, as the devil does holy 
 water, the "no patent, no pay" solicitors, and those 
 who offer to get you full protection for about half 
 the regular fee. The first are like quack doctors; 
 the second, like shoddy dealers. Get your patent 
 through reputable solicitors, who will charge a good, 
 living price and give you something through which 
 the next comer cannot drive a circus wagon, band 
 and all. 
 
 Avoid shark patent-selling agents, particularly 
 the kind who charge you for examining and adver- 
 tising. Very few firms which sell patents will insist 
 on such a fee. It is of course desirable that any one 
 undertaking to sell a patent shall have, before he 
 undertakes it, some idea of two things: first, that it 
 is a good thing; and second, that the patent papers 
 are well drawn. But there are many cases where 
 
Perfecting and Developing 183 
 
 the inventor can show the agent, more plainly than 
 he could find out for himself, that the invention is 
 a good one; and the name of the firm which has 
 procured the patent papers should be the guarantee 
 that they are well drawn. There are of course 
 exceptions to most rules, and there are to this. But 
 whether you pay an advance fee or not, see that 
 the firm to which you offer the negotiation of your 
 patent is well connected and recommended, and has 
 already successfully done business on a cash basis 
 for other inventors. 
 
 Avoid, on the one hand, too great haste in getting 
 rid of your invention ; but, on the other, too great de- 
 lay. Do not let the sense of the importance of your 
 invention keep it on your hands for three or four 
 years after patenting. Remember that a patent, un- 
 like real-estate, never gets more valuable with years. 
 
 Before you spend much money — either your 
 own or any one's else — be sure: (1) that your in- 
 vention will work; (2) that no one else has patented 
 it; (3) that there is an opportunity for its sale; (4) 
 that there is not too much competition. 
 
 Many a man starts off and orders a fancy nickel- 
 plated model, and applies for his patent, only to find 
 that the idea will not work even the least little bit. 
 In this matter the advice of some one well up in the 
 theory, added to that of some one else well up in the 
 practice, would be valuable. 
 
 Many an application done up in all the bravery 
 of typewriting, notarial seal, and all that, has been 
 rejected like a bad penny for the very simple reason 
 
184 Hints to Inventors 
 
 that some one else had before patented the idea, or 
 something enough like it to bar out the newcomer. 
 It is cheaper to have the ground gone over first by 
 a preliminary search made by a competent person 
 even before the application is written out. 
 
 There are many good things which are very in- 
 genious, and perfectly novel and patentable, but 
 which are in lines in which there would not be 
 enough sale in ten years to pay the inventor the ex- 
 pense of getting out patents. Yet plenty of such 
 things are patented almost every week, in this coun- 
 try. Sometimes there could be but one customer, — 
 say the Government, or some great corporation, — 
 and there may be reasons which are obvious, and 
 others not so plain on the surface, why you could 
 not even make them a present of your invention. 
 
 There are some lines in which competition is so 
 fierce that there would not be any use in coming 
 into the field. If the Marquis of Worcester, Watt, 
 Fulton and Morse, Whitney and Howe, Edison 
 and McCormick, and a dozen more of the great in- 
 ventors of the world, past and present, were to put 
 their heads together, and get up a new car-coupler, 
 the chances are that they could not get thirty cents 
 for the patent. The thing is overdone. 
 
 You must bear some of the burden of the intro- 
 duction yourself. A capitalist may be willing to 
 bet his hard dollars that your idea will work, if you 
 have secured a patent; or he may be induced to bet 
 that it is patentable, if you show him that it will 
 work; but moneyed men who will bet that your in- 
 
Perfecting and Developing 185 
 
 vention is both patentable and practicable are few 
 and far between. If they make such a bet, it will 
 be with very heavy odds against the inventor. 
 
 Don't be unduly suspicious. Don't fear that 
 any one who takes more than a passing interest in 
 your invention is going to steal it. All business is 
 based more or less on trust. You trust some one 
 every day. So does every one else. There is no use 
 in your showing every Tom, Dick, and Harry what 
 you have, or expect to have; but if you show a man 
 anything at all, do it with trust. If he is not trust- 
 worthy, do not show him or tell him anything. 
 
 Don't take out a caveat. To do that simply offers 
 a premium on some one letting you have the luxury 
 of an interference suit. You pay ten dollars govern- 
 ment fee for a caveat, and your paper is filed- If 
 some one else puts in a patent application which in- 
 terferes with your caveat, and the clerk who filed 
 your caveat happens to remember your idea, you 
 are then notified that it is your special privilege to 
 defend your property. 
 
 Fight shy of patent-selling bureaus, the propri- 
 etors of which profess to be "very near" this, that, 
 and the other great head of a corporation, or of a 
 government department. Any man who has a good 
 thing to sell, and is of business habits and good ad- 
 dress, could get near enough to any one who wants 
 to know of new and good things to be able to show 
 what he has, and for the person addressed to be able 
 to reject it if it is not good. Men with a "pull" are, 
 as a general thing, to be avoided, particularly if they 
 
186 Hints to Inventors 
 
 brag thereof. There are of course men who have a 
 pull; they have it because they deserve it. But all 
 the pulls in the world would not pull invention from 
 the slough of worthlessness to the high ground of 
 merit; and men who have a really good pull with 
 really great men are not going to risk spoiling their 
 pull by showing them poor things; and as a general 
 thing the men with a pull are harder to get at than 
 the people with whom they have the pull. 
 
 In most cases the best way for the inventor is to 
 license others to use his patent, paying either so 
 much per thousand articles made, or so much for 
 the right to make in a certain State, or so much for 
 the right to apply the invention to certain things. 
 Thus, for an invention in the line of machine-made 
 shoes, so much per thousand pairs; for a driving- 
 wheel or something that once applied cannot be 
 moved, so much per State or per county (based on 
 the population); for a compound like celluloid, so 
 much for the right to make combs, so much for the 
 right to make collars and cuffs, etc. 
 
 What patents are worth is a question often asked ; 
 but there is no answering it. The inventor very sel- 
 dom places his estimate too low. Some men have 
 made milhons out of a single patent; others have 
 lost all that they could make and -borrow. There 
 has been about as much made in some lines, on roy- 
 alties paid by infringers, as by the inventor himself 
 — sometimes more. An invention in the hands of 
 some men might realize a hundred thousand dol- 
 lars' profit; worked by others, not one thousand. 
 
Perfecting and Developing 187 
 
 No one can look upon a block of land and say how 
 much could be made out of it by a skilful real-estate 
 boomer. The range in values of patents is even 
 greater than in those of land. The patent on an in- 
 vention which i^ based upon one owned by some 
 one else might not be worth the match that it would 
 take to set it on fire. While, of course, those who 
 have inventions of their own are glad to have them 
 made as valuable as possible, there are instances 
 where a thing already patented is so good, and has 
 cost so much to get it on the market, that the maker 
 does not want to bother with any improvements. 
 If a thing is twice as good as its rivals, and has the 
 field to itself, to the extent of the maker's ability to 
 manufacture it, there is very little inducement for 
 him to get up new designs, patterns, and plans for 
 the sake of making it a little better. The only time 
 for him to do that is when his rivals have got some- 
 where near him. 
 
 There may be those who think that in these pages 
 I discourage invention. I don't. But I think it 
 criminal to encourage people who have poor things, 
 or good things that would not be practicable to work 
 up, in spending time and money in inventing and 
 patenting. 
 
 There are very few inventions which can be well 
 worked up and worked out without the aid of draw- 
 ings; and too few inventors can make mechanical 
 drawings, no matter how crude, which will show 
 their ideas so well that they can be worked from by 
 pattern-maker or other mechanic. Another thing 
 
188 Hints to Inventors 
 
 which is very important in this connection : it is very 
 much easier to alter a thing on paper than in wood 
 or metal. Proper mechanical drawings of most in- 
 ventions can be made, and will reveal weaknesses 
 or excellences which would not at first strike the 
 mind. If you do make a drawing, be sure that it is 
 sensible and practical; that is, that it truly — even 
 if crudely — represents the object. A drawing which 
 shows the front and two sides and part of the back 
 of a machine or article is apt to be misleading — 
 to be worse than none at all. 
 
 If you find that you cannot work out the details of 
 what you want, call in outside help. There are 
 plenty of wise heads engaged in just that business 
 — criticizing and developing crude ideas. Where 
 an inventor may not be exactly able to draw, or even 
 to suggest, just what he wants, the professional ad- 
 viser, or any other good, sound, practical man who 
 is posted, may fill in the blank at once, or, what is 
 of equal importance, prevent the adoption of some- 
 thing which would not work well, or at all. 
 
 
Chapter XXXV. 
 
 SELLING PATENTS* 
 
 In undertaking to sell a patent for an inventor, 
 the "promoter," or whatever other name may be 
 given to the person who undertakes the task of turn- 
 ing the inventor's brains into money, often (and it 
 may be said generally) encounters several obstacles 
 which are, in fact, of such frequent occurrence as 
 to be considered almost inseparable from such trans- 
 actions. It might be interesting to recall some of the 
 difficulties which are met, with a view perhaps to 
 aiding some who have inventions which they wish 
 to sell to place their invention upon the market. 
 
 In the first place, the most difficult thing to per- 
 suade an inventor is that an invention has little value 
 of itself; that its value is what it may be made to pro- 
 duce by intelligent work at the right time, in the 
 right place, by the right people, and among the right 
 class of purchasers and users. There are few if any 
 inventions which anybody is lying awake at night in 
 the expectation of getting. People of the present 
 day are very comfortable; very well satisfied with 
 most things that they have. So it was with their 
 fathers ; so with their grandfathers before them. No- 
 body really needs anything. Nearly all of our actual 
 
 *Paper read before the Polytechnic Section of the American In- 
 stitute, New York, May 24, 1888, by Robert Grimshaw, President. 
 
 [ 189] 
 
190 Hints to Inventors 
 
 wants and necessities are gratified. Our present 
 wants are largely artificial; and while they are in- 
 creasing, and while we are willing to pay for the 
 gratification, we are not uncomfortable on account 
 of the lack of any single invention as yet unpro- 
 duced. Now if it be true of an invention that it has 
 little value of itself, it is still more so of a patent, 
 which is simply the title-deed to an idea, which title- 
 deed may or may not be valid or valuable. 
 
 I hope that it will be pardoned me if I make the 
 remark that the average inventor is so ingrained in 
 conceit as to stand very much in his own light. He 
 is bright and has individuality, although he may not 
 possess originality; but that fact has no bearing what- 
 ever upon the value of his patent. The brilliancy, 
 or popularity, or wealth of a man owning a house of 
 which he wishes to dispose has no bearing whatever 
 upon the selling- value of that property. All that the 
 purchaser wishes to know is: whether the property 
 has any value, whether that value is at least equal 
 to the price demanded, and whether the title is clear 
 and can be properly transferred in payment of the 
 purchase money. But the inventor's conceit very 
 often steps in between him and the buyer — at 
 times with such offensiveness as to render the com- 
 pletion of negotiation absolutely impossible, if the 
 purchaser has any self-respect, which is generally 
 the case. 
 
 Another thing which very often comes up when 
 an inventor is fixing a value upon his invention or 
 upon his patent is that he generally claims to have 
 
Selling Patents 191 
 
 spent years of labor in the development and accom- 
 plishment of the idea. Now the purchaser does not 
 care a sou marque for that, any more than the pur- 
 chaser of a house cares to know how many years it 
 took the builder to save up money to erect it. It 
 might have taken that inventor ten years to accom- 
 plish a certain result at which another would have 
 arrived in ten months or even ten weeks. It may be 
 the inventor's fault, or it may not, that the attain- 
 ment of a result consumed a large amount of time 
 or extended through a long period. But whether 
 it is his fault or his misfortune has no bearing upon 
 the market value of the invention. In fact, the state- 
 ment that an invention has taken years of labor to 
 accomplish might more truly be taken as indicating 
 the inventor's incapacity, and the probability that 
 if any improvement is desired it will take several 
 years more to effect it, instead of its being pro- 
 ducible upon short notice. 
 
 There is another thing which very often interferes 
 with the sale of patents, and perhaps more so with 
 realizing on those which come near to being demanded 
 by the public than with any others. Those people 
 who have the power to treat for the purchase of in- 
 ventions in such lines have such frequent applica- 
 tions made to them by inventors more or less com- 
 petent, having inventions more or less practicable, and 
 secured by patents more or less valuable, that they 
 are tired of being bored with offers of any kind of 
 patent; and an invention has to be not only unusu- 
 ally good, but backed by considerable personal in- 
 
192 Hints to Inventors 
 
 fluence in order to secure even the most hasty con- 
 sideration. 
 
 One of the first questions which is asked when 
 the negotiation of a patent is commenced is gener- 
 ally, "Is the invention practical? Will it work? 
 Will it keep on working ? Will it save time ? Or 
 money? Or trouble? Or risk?" One more impor- 
 tant query in this connection is as to practicability. 
 "Has it been tried? If so, when? Where? By 
 whom ? And under what practical working condi- 
 tions ?" If the inventor has only the idea, or a little 
 five-cent model, or perhaps only the ghost of the 
 idea that he is going to have an invention, it is 
 rather hard to induce any one to advance money 
 upon this immaterial article of property. I think it 
 was Oscar Wilde who referred most aesthetically to 
 "unkissed kisses." One would imagine that they 
 would have very little value; but they are just as 
 valuable, and just as tangible, as the "unthought 
 thought" — the thought which the inventor thinks 
 that he is going to think, and thinks that no one else 
 has thought before him. Some of these ideas (or 
 ghosts of ideas) against which the inventor wishes 
 the capitalist to plank down his hard dollars have 
 about as much substance as a piece of wind tied up 
 with a string; and the title-deed to such aerial prop- 
 erty would probably be difficult to record, estab- 
 lish, or sell. 
 
 A propos of title-deeds, it must be remembered 
 that a patent-paper is simply a record descriptive 
 of the property, and certifying that the landmarks 
 
Selling Patents 193 
 
 and boundary-lines were established and laid down, 
 and handed in to the Office of Record on a certain 
 date, by a certain person who made the statement 
 (based either on imagination or on strong presump- 
 tion) that he was the discoverer or originator of the 
 property to which the description and boundary- 
 lines refer. The mere possession of a piece of paper 
 issued by the United States Patent Office, and having 
 a handsome title-page with a blue ribbon and a red 
 seal, does not mean anything in particular. Patent 
 Office officials and employees are fallible, like other 
 men. Pieces of property worth millions of dollars 
 have been taken away from those who have been in 
 actual possession, by some one who has proved that 
 their title-deeds were imperfect. If this is the case 
 with realty which has always existed, and of which 
 the certainty of title increases with age, how much 
 more is it likely to be so with the title to only an idea ! 
 But as a general thing the inventor considers his 
 possession of a little piece of paper with a red seal 
 to place him beyond the possibility of any doubt, 
 and objects to paying the expenses of having this 
 title searched. 
 
 Another question which is most natural is, "Has 
 the invention been perfected ? Or is it still crude ; 
 and will it demand the delays and expenses of fre- 
 quent and radical changes, and the issue of more 
 patents upon these improvements?" The evolu- 
 tion of an idea is as interesting as that of man from 
 the monkey. It often undergoes more changes. It 
 very seldom emerges full blown from the inventor's 
 
194 Hints to Inventors 
 
 brain, and often the third or the fourth stage of evo- 
 lution bears very much less resemblance to the orig- 
 inal than man does to the primeval monkey from 
 which he is said to have descended (although per- 
 haps ascended may be the better word). 
 
 Another question which it is proper for the in- 
 tending investor to ask is this: "Is the man who 
 offers to sell the invention the owner? Is his title 
 clear? Or has he mortgaged a quarter-interest to 
 one person, one-eighth to another, and so on, for 
 the purpose of raising money to develop it, so that 
 there are against it either recorded or unrecorded 
 claims which might make it difficult for the pur- 
 chaser to do anything with it?" 
 
 Still another question : " Does the value of the in- 
 vention covered by or referred to in the patent de- 
 pend upon some other patent to which it is attached 
 in improvement or perfection ?" If this be so, it can 
 readily be imagined that such a patent could have a 
 value very much like that of a plot of ground entirely 
 surrounded by other pieces of property through 
 which the owner of the central plot has no right of 
 way. 
 
 One of the very hardest things of which to per- 
 suade an inventor is that no one can afford to invest 
 money in a" patent" which is not yet allowed. There 
 are a great many reasons why (although the in- 
 ventor may act in good faith) the issue might be 
 absolutely impossible. 
 
 There are very many instances where the applica- 
 tion, after having lain in the Patent Office for two or 
 
Selling Patents 195 
 
 three years, has been thrown out; and out of the 
 whole number of applications made, not one-third 
 is covered by papers issued. 
 
 The mere fact that there may be in the patent 
 records nothing which in the judgment of the in- 
 ventor, or in that of a competent title-searcher, may 
 conflict with his idea, is no proof that there may not 
 be something in every-day use that is unpatented, 
 and which is in fact so old as to be absolutely un- 
 patentable. Or there may be in the Patent Office 
 something now in process of examination which 
 may be identical with the idea towards the patent- 
 ing of which the inventor wishes money to be ad- 
 vanced. 
 
 Again, as regards the issue of patents : the Patent 
 Office may be "cranky." It may take a notion not 
 to patent a certain idea; and whether that idea is 
 reasonable or unreasonable has very little bearing 
 on the subject ; but the only way to compel the issue 
 of such patent is a most tedious and expensive one. 
 
 One thing tending to lessen the value of a patent 
 in its very earliest stages is that there may be very 
 few customers for the idea, sometimes only one, as 
 in the case of ordnance; and naturally the value of 
 an idea which is only salable to two or three people 
 is very much less than that of one which will suit 
 millions direct. 
 
 Then, again, there may be in the market some 
 other patented or unpatented thing that is just as 
 good as the invention offered, if not better; or that 
 may be just as good and very much cheaper; or that 
 
196 Hints to Inventors 
 
 may be controlled by the only person to whom the 
 patent which is offered for sale may be salable. 
 
 A patent may be most excellent in itself, but the 
 country may be already supplied with some other 
 invention and it may be impossible to make a change. 
 For instance : in the matter of continuous air-brakes 
 for railway-trains — if you were to have a patent 
 for a very much better invention than the existing 
 one used on all the great trunk lines, you would find 
 it perhaps difficult or perhaps impossible to intro- 
 duce it on any one line; because the present contin- 
 uous fines are already equipped with a particularly 
 satisfactory system, and as all roads wishing to do 
 business with connecting lines must be equipped 
 similarly with those other lines, it will be found im- 
 possible to change on any one line without making 
 the same change on all the others, which would in- 
 volve throwing away the present appliances and re- 
 placing them with the new. 
 
 It is of the utmost importance for a patent to be 
 properly taken out. The old saying that he who 
 conducts his own case in court has a fool for a client 
 applies with even greater force to the amateur pat- 
 ent solicitor. The chances are that such patent will 
 have no value as a title-deed. It is curious enough 
 that the man who would not dare prepare the title- 
 deeds to a piece of property worth only $2,000 or 
 $3,000 will attend to his own patent-soliciting in 
 taking out the papers for an invention which he 
 himself deems worth $40,000 or $50,000. 
 
 The inventor must bear in mind that no one is 
 
Selling Patents 197 
 
 going to be so interested in any patent as to go to 
 more trouble and expense than he himself is willing 
 to undergo to look into the matter under negotia- 
 tion. The inventor must present the matter fully 
 and freely; supply all necessary documents, mod- 
 els, drawings, specifications, testimonials, and state- 
 ments; and must not expect an intending purchaser 
 to put himself out — even to the expense of a post- 
 age-stamp — in order to find out anything about 
 the invention offered for sale. 
 
 The suspicion which so frequently characterizes 
 the inventor is a great bar to his progress. He too 
 often considers that the whole world is leagued 
 against him in order to prevent the introduction of 
 his patent ; or that whoever looks into it for the pur- 
 pose of buying is merely endeavoring to get points 
 from it, so as to enable him to steal the idea. As a 
 matter of fact, the world outside cares very little 
 one way or another about the inventor; he is to the 
 world at large either a nonentity or a crank. The 
 world at large cares neither for him, nor for his idea, 
 nor for the patent thereon. It simply regards him 
 as some one who intends to exploit the community 
 for as large a sum as possible; and it expects to be 
 bored concerning the invention; in some few cases 
 individuals hope to receive profit in return for this 
 boring, and for the money which they advance. 
 
 There is another thing which the inventor should 
 write in capital letters in his mind: that apologies 
 are no good. The invention must be ready to work. 
 It must work on sight when shown. There is no use 
 
198 Hints to Inventors 
 
 in trying to make the purchaser believe that the in- 
 dustrial world will have to be reorganized in order 
 to suit the imperfect work of a new invention. It 
 must do work that people call for. The purchaser 
 of an invention has enough to do to perfect and em- 
 body the thing mechanically and introduce it com- 
 mercially, without undertaking missionary work, 
 converting people in general to the inventor's theory 
 as to what should be produced, or how it should be 
 used. 
 
 A word of caution may be given even to the most 
 suspicious inventor, — transact no business in refer- 
 ence to either taking out or selling patents, except 
 with persons whose integrity is unquestionable. 
 Having once found such persons, do not be suspi- 
 cious of them. 
 
 For two reasons it is a bad plan to ask capitalists 
 to advance money upon an invention for the pur- 
 pose of patenting it. First, there is considerable 
 risk in the matter — much more than the inventor 
 thinks; second, such a course shows either poverty 
 or lack of faith upon the inventor's part in his own 
 invention. In either case he will get less for his pat- 
 ent than if he raises the money to perfect his title- 
 deeds in another quarter than the one where he ex- 
 pects to sell the invention. 
 
 A word as to caveats. The United States Patent 
 Office is in most respects very liberal to inventors, 
 and extends a helping hand to them in every way, 
 particularly in giving them six months between the 
 allowing of a patent and its final formal issue; but 
 
Selling Patents 199 
 
 in the caveat it lays a trap into which many an in- 
 ventor stumbles. A caveat is simply a piece of paper, 
 for which the government fee is ten dollars, certify- 
 ing that on a particular day the inventor lodged in 
 the Patent Office a paper descriptive of his inven- 
 tion. If at some time after the issuing of the caveat 
 and during the one year's period of so-called pro- 
 tection, some one else lodges in the Patent Office an 
 application which conflicts with the subject of the 
 caveat, and if the clerk who filed away the applica- 
 tion furnished by the caveat happens to be still in 
 the service and happens to remember that he filed 
 away such an application, then the inventor is no- 
 tified by the Government that he has the right to 
 commence an interference suit — one of the most 
 expensive things in which an inventor or his back- 
 ers can indulge. 
 
 The first government fee upon the application for 
 a patent is but five dollars more than that for the 
 caveat, and gives the inventor a status and a record. 
 There are very few caveats which have been issued 
 that are worth the paper upon which they are 
 printed. 
 
Chapter XXXVI. 
 MUD-GUARDS FOR AUTOMOBILES 
 
 The average mud-guard on automobiles is in- 
 tended to prevent the mud from splashing the oc- 
 cupants; but it does not protect the occupants of 
 other vehicles which may be in the neighborhood, 
 nor foot-passengers. Indeed, the motor-busses in 
 London splash everything within a radius of ten 
 feet, being in this respect by far worse than ordinary 
 motor-carriages, which, in turn, by reason of their 
 pneumatic rubber tires, are worse than horse-pro- 
 pelled vehicles. 
 
 Inventors should make a note of this fault, which 
 is one of the reasons why the London County Coun- 
 cil is refusing licenses to motor-busses — noise be- 
 ing the other and principal reason, 
 
 I 200 ] 
 
Chapter XXXVII. 
 
 INVENTION NEEDED BY THE 
 FRENCH GOVERNMENT 
 
 Some years ago the French government offered 
 a prize for a substance by which alcohol could be so 
 denatured as to be absolutely undrinkable without 
 being poisonous, and which should not materially 
 increase the cost of the spirit. This prize has not 
 yet been claimed, because there has been nothing 
 offered which comes up to the requirements, 
 which are, in detail, that it shall have a most charac- 
 teristic smell and taste, preferably also dye the spirit 
 some color which would make it unmistakable for 
 alcohol suitable for human consumption, shall not 
 interfere with the use of the spirit for illumination, 
 heating, or power-generating purposes, and shall be 
 absolutely non-neutralizable and not extractable 
 from the denatured spirit, by either mechanical 
 means — as filtering — or chemical treatment. 
 
 [ 201 ] 
 
Statistics of the Countries of the World 
 
 Countries 
 
 Population Sq . Miles 
 
 Capitals. 
 
 China 
 
 British Empire* 
 
 Russian Empire 
 
 United States 
 
 United States and Islands 
 
 Philippines 
 
 Porto Rico 
 
 Hawaii 
 
 Tutuila, Samoa 
 
 Guam 
 
 France and Colonies 
 
 France 
 
 Colonies ■ 
 
 Algeria 
 
 Senegal, etc 
 
 Tunis 
 
 Cayenne 
 
 Cambodia 
 
 Cochin-China 
 
 Tonquin 
 
 New Caledonia 
 
 Tahiti 
 
 Sahara 
 
 Madagascar 
 
 German Empire, in Europe . . 
 
 Prussia 
 
 Bavaria 
 
 Saxony '. 
 
 Wurtemberg 
 
 Baden 
 
 Alsace-Lorraine 
 
 Hesse 
 
 Mecklenburg-Schwerin 
 
 Hamburg 
 
 Brunswick 
 
 Oldenburg 
 
 Saxe-Weimar 
 
 Anhalt 
 
 Saxe-Meiningen 
 
 Saxe-Coburg-Gotha 
 
 Bremen 
 
 Saxe-Altenburg 
 
 Lappe 
 
 Reuss (Younger line) 
 
 Mecklenburg-Strelitz 
 
 Schwarzburg-Rudolstadt . . . 
 
 Schwarzburg-Sondershausen 
 
 Lubeck 
 
 Waldeck 
 
 Reuss (Elder line) 
 
 Schaumburg-Lippe 
 
 German Africa 
 
 Austro-Hunganan Empire 
 
 Japan 
 
 Netherlands 
 
 Netherlands and Colonies . 
 
 Borneo 
 
 Celebes 
 
 Java 
 
 426,447,000 
 
 396,968,798 
 
 129,004,514 
 
 t76,30 3 ,887 
 
 $89,000,000 
 
 8,000,000 
 
 953,243 
 
 i54,oo 
 
 5,5oo 
 
 9,000 
 
 65,166,967 
 
 38,641,333 
 
 21,448,064 
 
 4,700,000 
 
 183,237 
 
 1,900,000 
 
 26,502 
 
 1,500,000 
 
 2,323,499 
 
 12,000,000 
 
 62,752 
 
 12,800 
 
 1,100,000 
 
 3,500,000 
 
 58,540,000 
 
 34,472,509 
 
 6,176,057 
 
 4,202,216 
 
 2,169,480 
 
 1,867,944 
 
 i,7i9,47o 
 
 1,119,893 
 
 607,770 
 
 768,349 
 
 464,333 
 
 399,180 
 
 362,873 
 
 316,085 
 
 250,731 
 
 198,7 
 
 180,443 
 
 161,129 
 
 123,250 
 
 112,11 
 
 98,371 
 
 83,939 
 
 73,623 
 
 76,485 
 
 56,565 
 
 53,787 
 
 37,204 
 
 5,950,000 
 
 46,973,359 
 
 44,260,604 
 
 5,103,924 
 
 33,042,238 
 
 1,073,500 
 
 2,000,000 
 
 21,974,161 
 
 4,218,401 
 11,146,084 
 8,660,395 
 e ,99o 
 
 3,602, 
 
 3,756, 
 
 143, 
 
 3, 
 
 6. 
 
 3,250,000 
 
 204,092 
 
 2,923,679 
 
 184,474 
 
 580,000 
 
 45,ooo 
 
 46,697 
 
 40,530 
 
 23,160 
 
 119,660 
 
 7,624 
 
 462 
 
 1,550,000 
 
 28,500 
 
 208,830 
 
 134,603 
 
 29,282 
 
 5,787 
 
 7,528 
 
 5,821 
 
 5,6oo 
 
 2,965 
 
 5,137 
 
 158 
 
 i,425 
 
 2,479 
 
 1,387 
 
 906 
 
 953 
 
 760 
 
 99 
 
 5ii 
 
 472 
 
 319 
 
 1,13 
 
 363 
 
 333 
 
 115 
 
 433 
 
 122 
 
 131 
 
 822,000 
 
 264,595 
 
 147,669 
 
 12,680 
 
 778,187 
 
 203,714 
 
 72,000 
 
 50,848 
 
 Peking. 
 
 London. 
 
 St. Petersburg. 
 
 Washington. 
 
 Washington . 
 
 Manila. 
 
 San Juan. 
 
 Honolulu. 
 
 Paris. 
 Paris. 
 
 Algiers. 
 St. Louis. 
 Tunis. 
 Cayenne. 
 Saigon. 
 
 Hanoi. 
 Noumea. 
 
 Antananarivo. 
 
 Berlin. 
 
 Berlin. 
 
 Munich. 
 
 Dresden. 
 
 Stuttgart. 
 
 Karlsruhe. 
 
 Strasburg. 
 
 Darmstadt. 
 
 Schwerin. 
 
 Brunswick. 
 
 Oldenburg. 
 
 Weimar. 
 
 Dessau. 
 
 Meiningen. 
 
 Gotha. 
 
 Altenburg. 
 
 Detmold. 
 
 Gera. 
 
 Neu Strelitz. 
 
 Rudolstadt. 
 
 Sondershausen. 
 
 Arolsen. 
 
 Greiz. 
 
 Buckeburg. 
 
 Vienna. 
 Tokio. 
 The Hague. 
 The Hague. 
 
 Batavia. 
 
Statistics of the Countries of the World 
 
 (continued) 
 
 Countries 
 
 Population Sq . Miles 
 
 Capitals. 
 
 Moluccas 
 
 New Guinea 
 
 Sumatra 
 
 Surinam 
 
 Turkish Empire 
 
 European Turkey 
 
 Asiatic Turkey 
 
 Tripoli 
 
 Bulgaria 
 
 Egypt 
 
 Italy 
 
 Italy and Colonies 
 
 Abyssinia 
 
 Eritrea 
 
 Somal Coast 
 
 Spain 
 
 Spanish Africa 
 
 Spanish Islands 
 
 Brazil 
 
 Mexico 
 
 Korea 
 
 Congo State 
 
 Persia 
 
 Portugal 
 
 Portugal and Colonies . 
 
 Portuguese Africa 
 
 Portuguese Asia 
 
 Sweden and Norway 
 
 Sweden 
 
 Norway 
 
 Morocco 
 
 Belgium 
 
 Siam 
 
 Roumania 
 
 Argentine Republic 
 
 Colombia 
 
 Afghanistan 
 
 Chile 
 
 Peru 
 
 Switzerland 
 
 Bolivia 
 
 Greece 
 
 Denmark 
 
 Denmark and Colonies 
 
 Iceland 
 
 Greenland 
 
 West Indies 
 
 Venezuela 
 
 Servia 
 
 Liberia 
 
 Nepaul 
 
 Cuba 
 
 Oman 
 
 Guatemala 
 
 Ecuador 
 
 Hayti 
 
 Salvador 
 
 Uruguay 
 
 Khiva 
 
 353-000 
 
 200,000 
 
 2,750,000 
 
 57,i4i 
 
 33,559,787 
 
 4,790,000 
 
 16,133,900 
 
 1,000,000 
 
 3,154,375 
 
 9,700,000 
 
 32,449,754 
 
 34,970,785 
 
 4,500,000 
 
 660,000 
 
 210,000 
 
 17,550,216 
 
 437,000 
 
 127,172 
 
 18,000,000 
 
 13,546,500 
 
 10,519,000 
 
 8,000,000 
 
 7,653,600 
 
 5,428,659 
 
 11,073,68 
 
 5,416,000 
 
 847,503 
 
 7,376,321 
 
 5,136,441 
 
 2,239,880 
 
 6,500,000 
 
 6,069,321 
 
 5,700,000 
 
 5,376,000 
 
 4,800,000 
 
 4,600,000 
 
 4,000,000 
 
 3,110,085 
 
 3,000,000 
 
 3,312,551 
 
 2,500,000 
 
 2,433,806 
 
 2,417,441 
 
 2,288,193 
 
 72,445 
 
 9,780 
 
 33,763 
 
 2,444,8 
 
 2,096,043 
 
 2,060,000 
 
 2,000,000 
 
 1,600,000 
 
 1,600,000 
 
 i,574,34o 
 
 1,300,000 
 
 1,211,625 
 
 915,512 
 
 840,725 
 
 700,000 
 
 42420 
 
 150,755 
 
 170,744 
 
 46,060 
 
 1,652,533 
 
 63,850 
 
 729,170 
 
 398,873 
 
 37,860 
 
 400,000 
 
 110,665 
 
 425,765 
 
 189,000 
 
 56,100 
 
 70,000 
 
 196,173 
 
 203,767 
 
 i,957 
 
 3,218,130 
 
 767,316 
 
 85,000 
 
 802,000 
 
 636,000 
 
 36,038 
 
 951,785 
 
 841,025 
 
 7,923 
 
 297,321 
 
 172,876 
 
 124,445 
 
 314,000 
 
 n,373 
 
 280,550 
 
 46,314 
 
 1,095,013 
 
 331,420 
 
 279,000 
 
 256,860 
 
 405,040 
 
 15,981 
 
 472,000 
 
 24,977 
 
 14,780 
 
 101,403 
 
 39,756 
 
 46,740 
 
 118 
 
 566,159 
 
 18,757 
 
 35,ooo 
 
 56,800 
 
 44,000 
 
 81,000 
 
 46,774 
 
 144,000 
 
 9,830 
 
 7,221 
 
 72,112 
 
 22,320 
 
 Amboyna. 
 
 Constantinople. 
 
 Tripoli. 
 
 Sena. 
 
 Cairo. 
 
 Rome. 
 
 Rome. 
 
 Madrid. 
 
 Rio Janeiro. 
 City of Mexico. 
 Seoul. 
 
 Teheran. 
 Lisbon. 
 Lisbon . 
 
 Stockholm . 
 
 Kristiania. 
 
 Fez. 
 
 Brussels. 
 
 Bangkok. 
 
 Bucharest. 
 
 Buenos Ayres. 
 
 Bogota. 
 
 Cabul. 
 
 Santiago. 
 
 Lima. 
 
 Berne. 
 
 La Paz. 
 
 Athens. 
 
 Copenhagen . 
 
 Copenhagen. 
 
 Reykjavik. 
 
 Godthaab. 
 
 Caracas. 
 
 Belgrade. 
 
 Monrovia. 
 
 Khatmandu. 
 
 Havana. 
 
 Muscat. 
 
 N. Guatemala. 
 
 Quito. 
 
 Port au Prince. 
 
 San Salvador. 
 
 Montevideo. 
 
 Khiva. 
 
Statistics of the Countries of the World 
 
 (continued) 
 
 Countries 
 
 Population 
 
 Sq. Miles 
 
 Capitals. 
 
 600,000 
 
 145,000 
 
 Asuncion. 
 
 420,000 
 
 42,658 
 
 Tegucigalpa. 
 
 420,000 
 
 51,660 
 
 Managua. 
 
 600,000 
 
 20,596 
 
 San Domingo 
 
 309,683 
 
 19,985 
 
 San Jose. 
 
 285,000 
 
 3i,57i 
 
 Panama. 
 
 245,380 
 
 3,486 
 
 Cettinje. 
 
 Paraguay 
 
 Honduras 
 
 Nicaragua 
 
 Dominican Republic 
 
 Costa Rica 
 
 Panama 
 
 Montenegro 
 
 *These estimates of the population and area include the recently acquired 
 great possessions in Africa. fCensus of 1900. JEstimated for January 1, 1904. 
 
 Countries. Estimated 
 
 British Empire: Population. 
 
 Australasia 5,500,000 
 
 Canada 5,400,000 
 
 Cape Colony 2,400,000 
 
 Great Britain 41 ,600,000 
 
 India 295,200,000 
 
 So. African Republic 1,200,000 
 
 Population of the United States 
 
 States and Territories, 1900 
 
 by 
 
 Alabama 1,828,697 
 
 Alaska 63,592 
 
 Arizona 122,931 
 
 Arkansas 1,311,564 
 
 California 1,485,053 
 
 539,7oo 
 908,420 
 
 i84,735 
 278,718 
 528,542 
 
 2,216,331 
 154,001 
 161,772 
 
 1,821, 550 
 
 Missouri 3,106,665 
 
 Montana 243,329 
 
 Nebraska 1,066,300 
 
 Nevada 4 2 ,335 
 
 New Hampshire 411,588 
 
 New Jersey 1,883,669 
 
 New Mexico 195,310 
 
 New York 7,268,894 
 
 North Carolina 1,893,810 
 
 North Dakota 319,146 
 
 Ohio 4,157,545 
 
 Oklahoma 398,33 1 
 
 Oregon 413,536 
 
 Pennsylvania 6,302,115 
 
 Rhode Island 428,556 
 
 South Carolina 1,340,316 
 
 South Dakota 401,570 
 
 Tennessee 2,020,616 
 
 Colorado 
 
 Connecticut 
 
 Dakota 
 
 Delaware 
 
 District of Columbia 
 
 Florida 
 
 Georgia 
 
 Hawaii 
 
 Idaho 
 
 Illinois 
 
 Indiana 2,516,462 
 
 Indian Territory 392,060 
 
 Iowa 2,231,853 
 
 Kansas 1,470,495 
 
 Kentucky 2,147,174 
 
 Louisiana 1,381,625 
 
 Maine 694,466 
 
 Maryland 1,188,044 
 
 Massachusetts 2,805,346 
 
 Michigan 2,420,982 
 
 Minnesota 1,751,394 
 
 Mississippi 1,551,270 
 
 Total 176,303,387 
 
 Population Continental United States (including Alaska), 76,149,386 (1900); 
 Philippines, 8,000,000; Porto Rico, 953,243; Hawaii, 154, 001; Guam, 8,661; 
 American Samoa, 5,800. Total population, 85,271,093. Population 1904, esti- 
 mating Continental United States, about 90,000,000. 
 
 t Includes 91,219 persons in the mifitarv and naval service of the United 
 States. 
 
 Texas 
 
 Utah 
 
 Vermont 
 
 Virginia 
 
 Washington . . 
 West Virginia 
 Wisconsin . . . 
 Wyoming 
 
 3,048.710 
 276,749 
 343,641 
 
 1,854,184 
 518,103 
 958,800 
 
 2,069,042 
 92,531 
 
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 Offered for one invention, and 
 $10,000 for another. 
 
 WE ADVERTISE OUR 
 CLIENTS' INVEN- 
 TIONS FREE 
 
 All patents secured through us 
 are advertised Free in the 
 World's Progress, of Wash- 
 ington, D. C.,a magnificently il- 
 lustrated and widely circulated 
 Journal devoted to the interests 
 of inventors and consulted by 
 manufacturers and promoters 
 when purchasing patents. 
 Sample copy free. 
 
 ADVANTAGES OF 
 
 EMPLOYING A 
 
 WASHINGTON 
 
 ATTORNEY 
 
 Our office is near the U. S. 
 Patent Office, and we can secure 
 patents in less time and give 
 cases more attention than those 
 remote from Washington. We 
 also have the advantage of per- 
 sonal interviews with the Ex- 
 aminers and do not have to 
 depend on correspondence or 
 associates. 
 
 Highest Indorsements 
 from Satisfied Clients, and 
 Recommendations from 
 Manufacturers, U. S. Sen- 
 ators, and Congressmen. 
 
 EVANS, WILKENS & CO. 
 
 REGISTERED PATENT ATTORNEYS 
 MAIN OFFICES, 835 F STREET, WASHINGTON, D. C. 
 
 New York Offices, 132 Nassau Street, New York City 
 
JUL li 
 
 'cerroa toc*t wv 
 JUL 30 1907 
 
 AUG 2 ISO?