Inventors at Work, with Chapters on Discovery

by George Iles

A generation ago much was said about functional diseases, it being supposed that apart from the mechanism of bone, muscle or nerve, the bodily functions might go astray of themselves. Improvements in the microscope have shown that many of these derangements are due to diseases of structure; and beyond the range of the microscope a careful study of symptoms enables the physician to infer that physical structures are affected in modes which, one of these days, he may be able to see and picture.

An eminent oculist, Dr. Casey A. Wood of Chicago, tells me that certain diseases of the brain and kidneys derange the sight in a way clearly revealed by an opthalmoscope, a small instrument by which the interior of the eye may be explored through the pupil. Thus a patient complaining of imperfect vision may be really suffering from an ailment involving much more than the eyes.

A noteworthy group of physicians devote themselves to the care of the insane, that is, of patients whose brains are diseased. As a general rule when insanity declares itself, manners depart first, then morals, and finally the physical powers of the eye, the ear, the hand. All in reverse telling the story of how mankind became human; first in developing the faculties shared with bird and beast, then in rearing character, and at last, in adding the graces of behavior.

Profit in Contraries.

From this digression into matters of astronomy and of the human body and mind, let us return to the workshop and the engine-room. There is gain, as we have seen, when an inventor takes a familiar process, like planing, and reverses it, so that instead of the plane moving across a board, the board is moved beneath a planer. Not seldom, too, profit has followed upon adopting a plan just the contrary of a time-honored practice, as when a Frenchman pierced a needle with an eye near its point instead of away from its point, taking a step that did much to make the sewing-machine a possibility. Guns were loaded at the muzzle for ages, until one day a man of daring loaded them at the breech, to find that method preferable in every way. A bullet or ball might then be larger and closer in fit than before, have greater velocity and penetration, while truer in flight, especially if sped from a rifled gun. Anything left in the gun was in front of the new charge instead of behind it. In manufacture, the perishable parts of the gun, its vent and the adjacent steel, are now in a movable breech-piece where they may be replaced with little cost and trouble. Loading and firing may be much more rapid than with muzzle-loaders, while less space is required and the gunners are much less exposed than formerly. And ages before there was such a thing as a firearm, a vast stride in tilling the ground was taken simply by reversing an ancient practice. At first the soil was scratched by a stick drawn along its surface; when some primeval Edison gave the stick a forward instead of a backward thrust he created the plow, and tillage began in earnest.

In feeding coal to a fire, as in the case of a common grate, the one plan for centuries was to add the fuel from above. As gradually heated by the glowing mass beneath it, this fresh fuel sent forth comparatively cool gases which, to a considerable extent, passed into the chimney without being burnt. A mechanical stoker of the underfeed type forces fresh coal beneath the fuel already aglow; the result is that all the gases from the fresh coal pass through an incandescent bed which heats them highly, so that on emergence into the air-current they are thoroughly consumed.

Link Belt Machinery Co.‘s Shop, Chicago, showing Sturtevant ventilating and heating apparatus.

In large machine shops a heating system is finding favor which equally departs from traditional methods. In a small workshop piping filled with steam or hot water serves well enough: in a lofty machine shop it serves badly, sending as it does warm currents of air toward the roof where warmth does only harm. The union of a fan with a system of steam coils introduces a vast improvement. Air warmed to any desired temperature is carried in ducts throughout the building, with outlets at the points most in need of heat. Instead of being allowed to take its way to the roof, the warmed air is forcibly directed to the floor which otherwise would be unduly cool. Because the air is in rapid motion the heating coils may not be more than one fourth as extensive as for a system of direct radiation. This plan has the further advantage of utilizing exhaust steam without producing undue back pressure on the pumps or engines, and yields results almost equal to those from live steam. See accompanying [illustration].

Lighting as well as heating may share the gain of changing an old method for its contrary. Many forms of reflectors, both in glass and metal, have been designed to scatter the beams of lamps, usually in a downward direction. An excellent plan directs the positive carbon of an arc-lamp to the ceiling instead of to the floor; from the ceiling, duly whitened, the rays descend more thoroughly and agreeably diffused than if reflected from mirrors or refracted by prisms, however ingeniously shaped and disposed. See [illustration] on page 75.