Simplicity always desirable, except when it costs too much ... Taking direct instead of roundabout paths. ... Omissions may be gainful ... Classification and signaling simpler than ever before.

For a simple task the inventor’s means should be as simple as possible. Mr. J. J. Thomas in his “Farm Implements” says:—

Simplicity of Build Desirable.

“After a trial of a multitude of implements and machines, we fall back on those of the most simple form, other things being equal. The crow-bar has been employed from time immemorial, and it will not likely go out of use in our day. For simplicity nothing exceeds it. Spades, hoes, forks are of similar character. The plow, though made up of parts, becomes a single thing when all are bolted and screwed together. For this reason, with its moderate weight, it moves through the soil with little difficulty—turning aside for obstructions, on account of its wedge form, when it cannot remove them. The harrow, although composed of many pieces, becomes a fixed, solid frame, moving on through the soil as a single piece. So with simpler cultivators. Contrast these with Pratt’s ditching machine considerably used some years ago, but ending in failure. It was ingeniously constructed and well made, and when new and every part uninjured, worked admirably in some soils. But it was made up of many parts and weighed nearly half a ton. These two facts fixed its doom. A complex machine of this weight moving three to five feet per second, could not strike a large stone without a formidable jar, and continued repetitions of such blows bent and deranged the working parts. After using a while, these bent portions retarded its working; it must be frequently stopped, the horses becoming badly fatigued, and all the machines were finally thrown aside. This is a single example of what must always occur with the use of heavy complex machinery working in the soil. Mowing and reaping machines may seem to be exceptions. But they do not work in the soil, or among stones; but operate on the soft, slightly resisting stems of plants. Every farmer knows what becomes of them when they are repeatedly driven against obstructions by careless teamsters.”

Simplification Has Limits.

In discussing form we saw that simple shapes, such as those of sticks cut from a cylindrical tree, are not so strong as the less simple forms of hollow cylinders. We found that a joist, of plain rectangular section, is not so good a burdenbearer as a girder whose section resembles the letter I. If a slide for a timber is to be built on a mountain side, a novice would suppose that a straight inclined plane would afford the speediest path for the descending wood. Not so. More speedy is a slide contoured as a cycloid, the curve traced by a pencil fastened to the rim of a wheel as the wheel rolls along a floor beside a wall against which the pencil presses.

Not all tasks are simple, so that it is often best to build and use a machine as complicated as a turret-lathe or a Jacquard loom. Whatever the inventor seeks first, last and all the time is Economy; to that end he adopts whatever means will serve him best, whether simple or not. Professor A. B. W. Kennedy, famous as a teacher of machine design, says:—

“Simplicity does not mean fewness of parts. Reuleaux showed long ago that with machines there was in every case a practical minimum number of parts, any reduction below which was accompanied by serious practical drawbacks. Nor is real simplicity incompatible with considerable apparent complexity. The purposes of machines being continually more complex, simplicity must not be looked upon as absolute, but only in its relation to a particular purpose. There are many very complex-looking pieces of apparatus which work so directly along each of their main branch lines that they are in reality simple. It is usual that the first attempt to carry out a new purpose results in a very complicated machine. It is only by the closest examination of the problem, the getting at its very essence, that the machine can be simplified. If a problem is only soluble by extremely complicated apparatus, it becomes a question whether it is worth having. Closely allied to simplicity is Directness. Certain transformations are unavoidable, but the fewer the better. In some cases they may be as indispensable as the abused middleman in matters economic. In the first machine to do something mechanically hitherto done by hand, the error is often made of trying to imitate hand-work rigorously. The first sewing-machine was, I believe, made to stitch in the same way as a seamstress. It was not until a form of stitch suitable for a machine, although unsuitable for the hand, was devised, that the sewing-machine was successful. The first railroad carriages were practically stage-coaches put on trucks, from which the present carriages have only very slowly been evolved.”

Directness.

A few years ago it was usual to attach pumps, dynamos, and other machinery to their actuating engines by pulleys and belts. To-day in most cases the connection is direct; all the energy which would be absorbed by intervening wheels and leather is saved. In steam-turbines one and the same shaft carries the steam-vanes and the armature of an electrical generator. In saw-mills of modern design a very long steam cylinder is provided with a piston directly attached to the saw carriage. The same principle gives high economy to the steam hammer and pile-driver of Nasmyth. Hammers, drills, cutters and other tools driven by compressed air are directly attached to the rod which holds the piston. In like manner Saunders’ channeling machine, actuated by steam, has its cutters attached to its piston, so that a blow is dealt with no intervening crank-shaft, lever or spring.

Direct, too, is the binding machine for magazines and cheap books, which simply stitches with wire the whole together at the back, as if so many thicknesses of cloth. With the same immediacy we have wall-papers printed directly from the oak or maple they are to represent. Indeed, veneers are now so cheap and good as to be used instead of paper as wall coverings. In the province of art Mr. Hubert Herkomer has accomplished a notable feat in the way of directness, dispensing with the camera, or any of the etcher’s preliminaries of biting or rocking. He paints in monochrome on a copper plate as he would on a panel or canvas, covers his painting with fine bronze powder to harden the surface, from which he then takes an electrotype.

A supreme feat of directness was the invention of a machine which relates itself to art, science and business, the phonograph. Forty years ago Faber constructed a talking machine of bellows to imitate the lungs, with an artificial throat, larynx, and lips affording a weird and faulty imitation of the voice. Edison, bidding sound-waves impress themselves directly on a plastic cylinder, reproduces human tones and other sounds with vastly better effect. Faber sought to copy the method of voice production. Edison set himself the task of taking tones as produced and making them impress a surface from which they can be repeated at will.

Contrivances Which Pay a Double Debt.

A lamp commonly used by camping parties, and well worthy of wider employment, is at once a source of heat and light; while it boils a kettle it sheds an ample beam upon one’s table or book. Just this union of two services may be found in the crude lamp of the Eskimo.

Many processes of manufacture once separate are now united with economy of time and power. Steam cylinders for mangling, ironing and surfacing paper, effect smoothing and drying at one operation. Green lumber for making furniture is bent and seasoned at the same time. Wire is tempered as drawn. At first reflectors were distinct from lamps; in an excellent form of incandescent bulb the upper part of the container is silvered, increasing the efficiency of reflection in decided measure, as shown on page 75.

Ascertaining Solid Contents.

Sometimes an indirect path is better than a direct course; or, as the sailors say: “The longest way round is the shortest way there.” We can readily measure the contents of solids which are regular or fairly regular of outline. It is easy to compute or estimate the contents of a stone as hewn by a mason to form part of a wall, but to find the volume of a rough boulder by direct measurement is too difficult a task to be worth while. Let us have recourse, then, to an indirect plan which goes back to Archimedes: it will remind us of how the casting process evades the toil of chipping or hammering a mass of metal into a desired form. We take a vessel of regular shape, preferably a cylinder, duly graduated, and partly fill it with water. Any solid, however irregular, immersed therein, will at once have its contents declared by the height to which the water rises in its container, the water-levels before and after the immersion being compared. Incidentally we here have a means of ascertaining specific gravities. Weigh this body before and during immersion; comparison of the two quantities will tell the specific gravity of the body, that is its density as compared with that of water. For example a mass of iron which in air weighs 7.75 pounds will in water weigh 6.75 pounds, so that the specific gravity of iron is 7.75, the difference between the two weights being unity.

Sometimes we wish to know the solid contents of a body which will not bear immersion in water; a mass of gum, for instance. In such a case we immerse the body in a graduated vessel filled with fine dry sand, carefully sifted free of hollow spaces. Both before and after immersion the sand is brought to a level which is carefully noted. The difference between these levels, measured in the graduations of the container, gives the solid contents of the immersed body.

Measuring Refraction.

The degree in which a crystal, or a particular kind of glass, bends a beam of light is usually measured by giving the crystal or glass the form of a prism, through which rays are sent. Sometimes a crystal is so small and irregular that this method is not feasible. Then the inquirer resorts to an indirect plan. He immerses the crystal in liquids which he mixes until the crystal disappears through ceasing to bend light differently from the surrounding bath. He then fills a hollow glass prism with this liquid, and in noting its refraction he learns that of the immersed crystal.

Omission of Needless Elements.

A fresh eye, with a keen brain behind it, often detects wasted work in a process long sanctioned by tradition. At the Tamarac Copper Mine, in Northern Michigan, some new ore-crushers were needed in 1891. Among the engineers who sought to furnish these machines was Mr. Edwin Reynolds, of Milwaukee, whose improvements of the Corliss engine have made him famous. That he might see ore-crushers at work for the first time in his life, he visited the Tamarac mine. He observed that the stamps were built on an immense bed of costly timbers and rubber sheets, supposed to be indispensable to efficiency. His eye, unwarped by harmful familiarity, utterly condemned this elastic foundation. He at once proposed to discard both timbers and rubber, and rear new crushers directly on a vast block of solid iron. This heresy quite shocked the directors of the Tamarac Company; they stood out against Mr. Reynolds’ plan for two years. Then, with profound misgivings, they allowed him to erect a stamp of the cheap and simple pattern he had suggested, so laying the iron bed that, in case of its expected failure, work would be delayed not more than two days. Up went the Reynolds’ stamp, and out poured sixty per cent. more crushed ore than from a preceding machine using the same power. Instant by instant its energy was wholly exerted in crushing rock, not largely in the useless compression of an enormous elastic bed.

Long before there was any Tamarac Mine, inventors had bothered themselves providing for difficulties as imaginary as those which, at vast outlay, were met by the timber underpinning of old-time ore stamps. In 1825 the builders of locomotives at Easton, in England, provided their engine-wheels with teeth which worked into racks with corresponding projections. They were afraid that a smooth wheel on a smooth track would slip without onward motion. Their unnecessary gear was discarded when it was found that under a heavy engine a smooth wheel has adequate adhesion on a rail as smooth as itself. Toothed wheels and racks are now only at work on the railroads of Mount Washington and other steep acclivities. As James Watt used to say to William Murdock, his trusted lieutenant,—“It is a great thing to know what to do without. We must have a book of blots—things to be scratched out.”

Printers Abandon Useless Work.

Daily newspapers in part owe their cheapness to an omission that at first seemed bold enough. For many years printing paper, made in continuous rolls each of a mile or more, used to be cut into sheets, fed one by one to the press. It was a long stride in economy when the printer left the roll alone, and let an automatic press feed itself from the unwinding paper, cutting off a sheet only after the printing.

Electricity Used as Produced.

A parallel example is recorded in the twin art of telegraphy. At first it was believed that two wires were indispensable for a circuit. Steinheil showed that a single wire suffices if its terminals are soldered into plates buried in the ground. Thus, at a stroke, by impressing the earth into the service of electrical communication, he reduced the cost of telegraphic lines by one half. In another field the electrician has given himself a good deal of trouble in vain. As it originally streamed from voltaic batteries, the electric current had always a single direction; it was, to use a familiar phrase, a direct current. But when Faraday invented the first dynamo, and produced electricity from mechanical motion instead of from more costly chemical energy, the current was not direct but alternating; that is, its pulses came at one instant from the positive pole, the next instant from the negative. Inventors took great pains in devising apparatus to convert these alternating pulses into a direct current such as that yielded by a voltaic battery. To-day the alternating current for many important purposes, including transportation, is employed just as it leaves the dynamo. Such a current usually has comparatively high tension, at which transmission is much more economical than at low tension, small conductors serving instead of large ones. This advantage in many cases more than offsets the loss entailed by reversal of the magnetic field at each alternation; a loss but small when iron for the electro-magnets is well chosen.

Short Cuts in Engineering.

Rock may be so hard as to withstand a drill of the hardest steel; then the engineer pours an acid of the necessary dissolving power. A water pipe may freeze at a point difficult of access; it is thawed by the warmth created by an electric current. A surveyor has to reduce to square feet the irregular area of a factory site or a garden plot; around the edge of his diagram he runs a planimeter, it tells him automatically what surface it has surrounded in its excursion. If he has no planimeter, a delicate balance will serve just as well. Let him take a piece of paper, uniform in thickness, and cut it into the shape of the area in question. In weighing the diagram with care he learns its superficies because he knows the weight of each square inch or foot of the paper. Pumps for ages have exercised the wit of inventors who have devised wheels, screws, pistons, and scoops of every imaginable form. M. Giffard boldly discarded all moving parts whatever and in his injector, actuated directly by a blast of steam, provided a capital means of sending water into a boiler.

A generation ago engineers of eminence were attempting the transmission of energy in a variety of ways. Ropes and wire cables were installed for considerable distances in Germany and Switzerland; in France there was an extensive piping of compressed air, still in evidence at the capital; and water under high pressure is to some extent to-day employed in London. All these schemes, together with the old methods within a shop itself of taking motion from motor to machine by belt or chain, have been wiped off the slate by the electrical engineer. With a tax of the lightest he carries for many miles in a slender wire a current whose energy takes any form we please,—not only mechanical motion, but chemical action, light or heat. Can simplification go farther than this, or the future hold for us another gift as golden?

Painting by Immersion.

Binders, reapers, and mowers have irregular surfaces which it would be costly to paint by hand. Even to use the painting machine which works by compressed air would be somewhat expensive. In the painting shop of a factory both brushes and nozzles are banished. The large floor is fitted up with a series of tanks: overhead are the lines of a suspension railway. The tanks are filled with paint, the articles to be treated are run in on the rails, lowered automatically for their bath, and then carried off to drip and to dry. In this way a large and complicated agricultural machine can be painted in a few seconds. Were deep tanks employed, this method would squeeze oil, varnish, or paint into the pores of wood very thoroughly.

Churning the Air in a Telescopic Tube.

Astronomers suffer much from the inaccuracy of the images viewed in their telescopes in consequence of the disturbances in the atmosphere, common even in clear weather. Hence observatories have, of late years, been established at Arequipa, Peru, and at other stations where the atmosphere is calm and little disturbed by currents. On investigation Professor S. P. Langley, of Washington, discovered that a good deal of the perturbation of telescopic images arises from currents within the telescopic tube itself. As a remedy he adopted the heroic, yet simple, measure of thoroughly stirring up the air in the tube by a blower or other suitable means. Its air, thus brought to uniformity of condition, yielded images much clearer than those usually obtained. Especially convincing in this regard are capital photographs of artificial double stars whose beams were entirely confined within a horizontal tube in which they traveled to and fro through no less than 140 feet of churned air. These pictures showed that the disturbance within the tube itself appeared to be wholly eliminated by the device of vigorously stirring the air column.

This recalls a method of shipping pianos in refrigerator cars. The instruments are carefully brought to the temperature of the car, which is maintained at about zero, Centigrade. When the pianos arrive at their destination they are slowly warmed to the temperature of common air. No matter how long they have been cold, they suffer no hurt; for it is not cold, or moderate elevation of temperature, that does harm so much as uneasy fluctuations from one to the other.

Loose Cards Replace Books.

When one visits a public library, the title of a particular book is found in the catalogue in a moment. Every book as acquired has its title written on a card, and thousands of such cards are placed in alphabetical order, just like the words in a dictionary. A thousand cards or so begin with “A,” and are placed in a drawer marked “A,” which stands first in the case, and so with the rest. There is always room to spare in each drawer, so that when a card for a new book comes in there is space for it. It was a happy thought of a Dutch inventor when he thus made an index which can always be alphabetical, easily added to or subtracted from, simply because its leaves are mere cards with the binding of a common index omitted. In public libraries the catalogue-cards are of standard sizes, so also are the drawers in which these are disposed. In fact library-furniture of all kinds is to-day thoroughly standardized in its styles and dimensions, making it easy to fit up or to extend a library whether public or private.

The use of cards, or slips for like purposes, has passed from the library to the business office, the study, the housekeeper’s desk. Merchants keep their customers’ names on this plan, so as to send them price lists from time to time. Depositors in banks, policy-holders in assurance companies, tenants of real estate in cities, members of clubs, are all recorded in this simple and accessible fashion. Some great manufacturing houses receive a million letters in a twelvemonth; an adaptation of the card-index makes any single letter accessible in half a minute at most. To an extent which steadily grows, the same plan is ousting the old-fashioned ledgers from our offices; in their stead we are now using series of movable leaves which are removed when filled, giving place to new leaves in an unbroken round.

A good many readers make notes as they go. If these are written in books they soon become so numerous, so various of topic, as to demand laborious indexing. It is better to take the notes in a form which will index itself. Slips of good paper can be bought at low cost, and, as in the accompanying illustration, “Astronomy,” “Glass,” “Photography,” or other headings may be adopted. All the slips under a given head are numbered consecutively. Kept on edge in a shallow box, or tray, they are self-indexing, and a new slip takes its proper place at once. From its compactness this kind of note-keeping puts a premium on the abbreviations which suggest themselves in a special study.

Unit Systems.

A card system employed as a catalogue, or for account keeping, is made up of simple units which may be added to or deducted from with utmost ease. They may be manipulated as readily as the bricks, all alike, with which a child builds a house, a box, or a steeple. This principle a few years ago was extended to book-cases, each about a foot high and about thirty-three inches long; while each formed a unit by itself it could be combined with other such units to furnish forth a library. This plan had been adopted for office furniture of all kinds,—cabinets in which papers may be filed away, or which are divided into pigeon-holes for blanks and the like. In some handsome designs a unit unfolds as a small writing desk, while adjacent units contain drawers of various sizes. Each unit is so moderate in dimensions as to be readily portable; a dozen, a score, a hundred may be joined together to equip a sitting-room or the cashier’s office in a bank.

Numbering as a Fine Art.

When an American visits London for the first time, he may fall into an error which will much provoke him. Suppose that he has to call at 457 Strand. He begins at number 1 in that thoroughfare, and proceeds a goodly distance when, to his dismay he observes that the numbers he is passing on his right are strictly consecutive,—100, 101, 102 and so on. A weary trudge brings him to 457, opposite number 1, whence he started. That odd numbers should be on one side of the street, and even numbers on the other, did not occur to the city fathers of London centuries ago. In this regard a forward step was taken in Philadelphia, where the streets parallel with the Delaware River are First, Second, and so on, while each house on the streets crossing them from the river westward is so numbered as to tell between what streets it stands. Thus, when we walk up Chestnut Street, the first door above Ninth Street, on the right, is 901, although the house next below it, across Ninth Street, is 839; and so on with all parallel streets. If the thoroughfares in Philadelphia, running at right angles to the Delaware River, were labeled avenues, and consecutively numbered, the system would be a troublesaver indeed.

In New York the cross streets as they run east or west of Fifth Avenue are named east or west. In crossing each avenue eastward or westward the numbers jump to the next whole hundred, as in Philadelphia. The building at the southwestern corner of Third Avenue and East 23rd Street is 162; that on the eastward corner, opposite, is 200. Thus in cross streets the number of a house tells us between which avenues it will be found.

In hotels and office-buildings, throughout America, the numbering greatly aids an inquirer. Room 512, for example, will be found on the fifth floor; immediately beneath is 412 on the fourth floor; directly above is 612 on the sixth floor, the first figure always denoting the floor.

Classifying Books.

A capital use of numerals to convey information is that devised by Melvil Dewey, formerly State Librarian of New York at Albany. He divides literature into ten great departments, giving each of them one of the ten numerals. History, in this scheme, is represented by 9 as the first figure in the number of a book; the second figure refers to the geographical division to which the work belongs, thus 7 means North America; the third figure standing for the political division treated by the book, 1 representing the British Empire. A work on Canadian history, therefore, will bear as its number, 971.

An Advance in Scientific Signaling.

Everybody knows what a money-saver is the familiar code of the ocean cables, by which “befogged” stands for “Will the property be advertised for sale?” reducing the toll by the cost of six words. Most of the terms in a code are not dictionary words, but such collocations of letters as “carthurien” and “brankstrop.” A new code devised by Mr. Charles G. Burke, of New York, proceeds upon the use of four numerals, 1, 2, 3, 4, which he transmits in the fewest signals possible to a cable, 1 is a dot; 2 a dash, 3 a dash-dot; 4 a dot-dash. This is how they look when received on paper in comparison with ordinary messages:—

It is the separate signal with the time consumed in its transmission which is the real unit of cost. The codes now in use employ words whose letters, as signaled, demand more than twice the time required by the Burke system. Thus 4221332, as transmitted by Mr. Burke, means “Advise creditor to prove claim and accept dividend,” for which but ten signals suffice. In the codes now in the hands of the public, an average word of seven letters would contain twenty-three signals. How wide is the variety of sentences possible in the new method? If the numerals are employed in permutations of seven figures, as 1342423, a Burke code will contain 16384 sentences; in permutations of eight figures, four-fold, and in permutations of nine figures, sixteen-fold as many, or 262,144 sentences, a variety much more ample than that of any other system. Mr. Burke finds that an average code message has 8 letters to a word, each word requiring about 25 electrical impulses in transmission; an average permutation on his system does not demand more than 10 impulses.

Mr. Burke has also devised a capital mode of simplifying telegraphic signals of all kinds. A message in the usual Morse code has dots, dashes and spaces, each produced by depressing a key for a short, a long, or a longer period. Mr. Burke interrupts a current with a key solely with dot-intervals; the periods during which the current is unbroken are, according to their length, dot-signals, dash-signals, or spaces:—