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PNEUMATICS AND PNEUMATIC MACHINES. · Inventions of the Century

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Section thirteen of Inventions in the Century. This is a LibriVox recording. All
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LibriVox recordings are in the public domain. For more information or to volunteer,
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please visit LibriVox dot org. Inventions in the Century by William Henry Dolittle,
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Pneumatics and Pneumatic Machines. The march of the human mind is slow, exclaimed
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Burke in his Great Speech on Conciliation with the Colonies. It was the beginning
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of the last quarter of the eighteenth century that he was speaking, and he
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was referring to the slow discovery of the eternal laws of providence as applied in
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the field of political administration to distant colonies. The same could then have been
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said of the march of the human mind in the realms of nature. How
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slow had been the apprehension of the forces of that kind but silent mother,
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whose strong arms are ever read to lift and carry the burdens of men whenever
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her aid is diligently sought. The voice of Burke was, however, hardly
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silent when the human mind suddenly awoke, and its march in the realms of
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government and of natural science since then cannot be regarded as slow. More than
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fifteen centuries before Burke spoke, not only had Greece discovered the principles of political
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freedom for its citizens and its colonies, but the power of steam had been
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discovered an experimental work been done with it. Yet when the famous orator made
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his speech, the Grecian experiment was a toy of kings, and the steam
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engine had just developed from this toy into a mighty engine in the hands of
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Walt. The age of mechanical in vengeance had just commenced with the production of
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machines for spinning and weaving. And yet, in view of the rise of
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learning and the appearance from time to time by the intellects in the highest walks
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of science, the growth of the mind of the time of useful machinery had
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indeed been strangely slow. Learning had revived in Italy in the twelfth and thirteenth
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centuries and spread westward in the fourteenth. In the fifteenth gunpowder and printing had
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been discovered, and Sclet, the famous scholar of Italy, and Erasmus,
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the celebrated Dutch philosopher, was the leading restories of ancient literature. Science then
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also revived, and Copernicus, the pole gave us the truth theory of the
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solar system. The sixteenth century produced the great mathematicians at astronomer's Tycho Braille and
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Dane, Cardan and Galileo, the illustrious Italians, and Kepler, the German
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astronomer, whose discovery of the laws of planetary motion supplemented the works of Bernicus
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and Galileo and illuminated the early years of the seventeenth century. In the seventeenth
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century appeared Torricelli, the inventor of the barometer Guerrica, the German inventor of
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the airpump Fahrenheit, the inventor of the mercurial Thermomeica bearing his name Leibniz,
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eminent in every department of science and philosophy, Eigens, the great touch of
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astronomer and philosopher, Pascal of France, and Sir Isaac Newton of England,
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the worthy successors of Kepler, Galileo and Calpernicus. And yet, with the
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exception of philosophical discoveries and a fewer experiments, the field of invention in the
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way of motor engines still remained practically closed. But slight has been the discoveries
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and experiments referred to. They were the mine from which the inventions of subsequent
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times were quarried. One of the earliest, and not the first pneumatic machines
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was the bellofs Its invention followed the discovery of fire and of metals. The
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bladders of animals suggested it, and their skins were substituted for the ladders.
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The Egyptians have left a record of a juice thirty four centuries ago, and
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its juice has been continuous ever since. Mention has been made of the cannon.
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It was probably the earliest attempt to obtain motive power from the heat.
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The ball was driven out of an iron cylinder by the inflammatory power of powder.
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Let a piston be substituted for the cannon ball, as was suggested by
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Ikens in sixteen eighty and by Papping in sixteen ninety, and the charge of
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powder so reduced that when it is exploded, the pistol will not be thrown
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entirely out of the cylinder. Another small explosive charge introduced on the other side
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of the pistoon to force it back, or let the cylinderfy vertical and the
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pisto be driven back by gravity. Means provided to permit the escape of the
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gas after it has done its work and means to keep the cylinder cool,
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and we have the prototype of the modern heat engines. The gunpowder experiments of
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Higgens and Papment were not successful, but they were the progenitors of similar intentions
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made two centuries thereafter. Jan Baptista van Helmont, a Flemish physician fifteen seventy
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seven to sixty forty four, was the first to apply the term gas to
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the elastic fluids which resemble air and physical properties. Robert Boyle, the celebrated
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Irish scholar and scientist and improver of the air pump, and Edwin Marriotte,
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the French physicist who was first to show that a feather and a coin will
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drop the same distance at the same time, and a reservoir exhausted of air.
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Where the independent discoveries of boils and Mariotte's law of gases sixteen fifty to
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sixteen seventy six. This was that at any given temperature of a gas which
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is at rest, its volume varies inversely with the pressure put upon it.
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It follows from this law that the density and tension, and therefore the expansive
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force of a gas are proportional to the compressing force to which it is subjected.
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It is said that abbe Houtevil, the sun of a baker of or
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Leon about sixteen seventy eight, proposed to raise water by a powder boulder,
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and that in sixteen eighty two we described a machine based on the principle of
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the circulation of the blood produced by the alternate expansion and contraction of the heart.
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The production of heat by concentrating the rays of the sun. If a
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burning objects had been known from the time of Archimede, and been repeated from
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time to time. Thus stood this art at the close of the seventeenth century,
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and thus it remained until near the close of the eighteenth. In England,
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Murdoch the corner steam engineer was the first to make a use coal gas
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for illuminating purposes, which he did in seventeen ninety two. In seventeen ninety
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eight, its utilization for other practical purposes was then suggested. Gas engines as
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motive powers were first described in the English Pattern to John Barber in seventeen ninety
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one, and then in one issue to Robert Street in seventeen ninety four.
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Barbara proposed to introduce a steam of carbonated hydrogen gas through one port and a
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quantity of air in another, and exploded them against the piston. Street proposed
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to drive up the piston by the expansive voice of a heated gas and anticipated
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many modern ideas. Felipe Lebon, a French engineer in seventeen ninety nine and
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eighteen o one, anticipated in a theoretical way many ideas since successfully reduced to
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practice. He proposed to use coal gas to drive a piston, which in
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turn should move the shaft that worked the pumps, which forced in the gas
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in air, and thus make the machine double acting, to introduce a charge
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of inflammable gas mixed with sufficient air to ignite it to compress the air and
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gas before they entered the motor cylinder, to introduce the charge alternately on each
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side of the piston, and he also suggested the use of the electric spark
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to fire the mixture. But Lebon was assassinated and did not live to work
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out his ideas. At the very beginning of the nineteenth century, John Dalton
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in England eighteen o one to eighteen o seven and gave the Sack in France
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began their investigation of gases and vapors. Dalton was not only the author of
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the atomic theory, but the discover of the leading ideas in the constitution of
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mixed gases. These features with the diffusion of gases, the action of gases
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on each other in vacuum, the influence of different temperatures upon them, their
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chemical constituents, and their relative specific gravity. He Basah, continuing his investigations
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as to expansion of air and gases under increased temperatures, in eighteen o seven
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to ten, established the law that when free from moisture, they all dilate
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uniformly and to equal amounts for all equal increments of temperature. He also showed
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that the gases combined as to volume in simple proportions, and that several of
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them, on being compounded, contracted always in such simple proportions as one half,
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one third, or one quarter of their joint bulk. By these laws
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are forms of engines which were made to work through the agency of heat are
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classed as heat engines, so that under this head are included steam engines,
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air engines, gas engines, vapor engines, and solar engines. The tide
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that binds these engines into one great family is temperature. It is the heat
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that does the work, Whether it is a cannon, the power of which
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is manifested in a flash, or the slower moving steam engine, whose throving
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heart beats not until water is turned to steam, or the sun, the
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palent of them all, whose rays are grasped and used to erect The question
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in all cases is what is the amount of heat produced? And how can
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it be controlled? It then, can make no difference what the agent is
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that is employed, whether air or gas for steam, or the sun or
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gunpowder explosion, but what is the temperature to be attained in the cylinder or
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vessel in which they work. Power is the measure of work done in a
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given time. Hoise power is the yeundit of such measurement, and it consisted
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the amount of power that is required to raise one pound through a vertical distance
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of one foot. This power is pressure, and the pressure is heat.
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The yieldit of heat is the amount of heat required to raise the temperature of
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a pound of distilled water one degree from thirty nine degrees to forty degrees fahrenheit.
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Its amount or measurement is determined in any instance by a damn themometer.
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These were the discoveries with which philosophy opened the nineteenth century so brilliantly in the
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field of pneumatics. Before that time it seemed impossible that explosive gases would ever
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be harnessed to steam had been and made to do continual successful work in the
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cylinder and behind a piston. As yet, means were to be found to
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make the engine efficient as a double acting one, to start the untamed steed
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at the proper moment, and to stop him at the moment he had done
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his work as Newcoleman had been the first in the previous entry to apply the
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steam engine to practical work pumping water from mines. Sir Samuel Brown of England
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was the first in the century to invent and use a gas engine upon the
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water. Brown took out patents at eighteen twenty three. In eighteen twenty six
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he proposed to use gunpowder gas as the motive power. His engine was also
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described in the Mechanics magazine published in London at that time. In the making
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of his engine, he followed the idea of a steam engine, that is,
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the flame of an ignited gas jet to create a vacuum within the cylinder
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instead of steam he fitted up an experimental boat with such an engine and means
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upon the boat to generate the gas. The boat was then operated upon the
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Thames. He also succeeded experimentally in adapting his engine to a road carriage,
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but bronze machines were cumbrous, complicated, and difficult to work, and therefore
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did not come into public use. About this time eighteen twenty three, Davy
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and Faraday reawakened interesting gas engines by the discovery that a number of gases could
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be reduced to a liquid state, some by great pressure and others by cold,
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and that upon the release of the pressure of the gases would return to
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their original volume. In the condensation heat was developed, and in re expansion
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it was rendered latent. Then right in eighteen thirty three obtained the patent at
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which he expounded and illustrated the principles of expansion and compression of gas and air
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performed in separate cylinders, the reduction of a vacuum by the explosion, and
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the use of a water jacket around the cylinder for cooling it. A.
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William Burdett in eighteen thirty eight has claimed the honor of having been the first
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to invent the means of compressing the gas at air previous to the explosion,
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substantially the same as adopted gas engines of the present day. The defects found
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in gas engines thus far were want of proper preliminary compression than in complete expansion
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of finally loss of heat through the walls. Some years later, Lennois,
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a Frenchman, invented a gas engine of a successful type, of which three
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hundred in eighteen sixty two were in use in France. It showed what could
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be accomplished by an engine in which the fuel was introduced and fired to directly
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the piston cylinder. Its essential features were cylinder into which a mixture of gas
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and air was admitted at atmosphere of pressure, which was maintained until the piston
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made half its stroke when the gas was exploded by an electric spark. A
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wheel of great weight was hung upon a shaft which was connected to the piston,
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and which weight abs of the force suddenly developed by the explosion and so
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moderated the speed. Another object of the use of the heavy wheel was to
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carry the machine over the one half of the period in which the driving power
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was absent. Hugon another eminent French engineer invented and constructed gas entered on the
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same principle as Linnaire's about this time. Eighteen fifty to sixty, Monsieur Beau
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de Rose, a French engineer, thoroughly investigated the reasons of the uneconomical working
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of gas modes and found that it was due to water, sufficient compression of
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the gas and air previous two explosion, incomplete expansion of laws of heat through
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the walls of the cylinder, and he was the first to formulate a cycle
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of operations necessary to be followed in order to render gas engine efficient. They
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related to the size and dimensions of the cylinder, the maximum speed of the
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piston, the greatest possible expansion, and the highest pressure obtainable at the beginning
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the act of expansion. The study and application of these conditions created great advancements
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in gas engines. With the discovery and development of the oil wells in the
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United States about eighteen sixty, a new fuel was found in the crude petroleum
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as well as the source of light. The application of petroleum two engines,
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either to produce furnace heat or as introduced directly into the piston cylinder mixed with
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inflammable gas to produce flame. Heat and expansion has given a wonderful impetus to
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the utilization of gas engines. G. H. Brayton of the United States
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in eighteen seventy three invented a very efficient engine in which the vapor of petroleum
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mixed with air constituted the fuel. Adolfspiel Berlin has also recently invented a petroleum
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engine. Principle among those to whom the world is indebted for the revolution in
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the construction of gas engines and its establishment as a successful rival to the steam
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engine, as Nicholas O Auto of tuiz On the Rye. In the Linare
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and Hugon system, the expansive force of the exploded gas was used directly upon
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the piston and threw this upon the other moving parts. A great noise was
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produced by these consults and explosions, and the autosystem. The explosion is used
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indirectly and only to produce a vacuum below the piston. When atmospheric pressure is
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used to give the return stroke of the piston and produce the effective work,
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the auto engine is noiseless. This is accomplished by his method of mixing it
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admitting the gases. He employs two different mixtures, one a feebly explosive mixture
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and the other a strongly explosive mixture, used to operate on the piston and
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thus prolonged the explosions. The mode of operation of one of Auto's most successful
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engines is as follows. The large flywheel is started by hand or other means,
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and as the piston moves forward, it draws into the cylinder a light
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charge of mixed gold gas and air, and the gas inlet is then cut
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off. As the piston returns, it compresses this mixture. At the moment
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the downstroke is completed, the compressed mixture is ignited and expanding drives the piston
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before it. In the second return stroke, the burnt gases are expelled from
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the cylinder and the whole made ready to start afresh. Work is actually done
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in the piston only during one quarter At the time it is in motion,
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the flywheel carries forward the work at the outset and the gearing the rest of
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the time. Otto is associated with Langon in producing his first machine, and
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its introduction at the Centennial Exposition of Philadelphia in eighteen seventy six excited great attention.
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Otto and E. W. And W. J. Croftsley jointly and
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then Otto Singly subsequently patented notable improvements. Simon Bishkoff and Clark Heard and Clayton
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in England, Demmler of deuts On, the Rhine, Biker and Vegan of
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the United States, and others have made improvements in the auto system. Ambl
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niacal gas engines have been successfully invented. Aqua ammonia is placed in a generator
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in which it is heated. The heat separates the ammonia gas from the water,
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and the gas is then used to operate a suitable engine. The exhaust
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gas is cooled, passed into the previously weakened solution, reabsorbed and returned to
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the generator. An eighteen ninety Charles Tayler of France patented and a more diacal
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engine also means for utilizing solar heat and exhaust steam for the same purpose,
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and in the same year Desussane, also of France, patented in an engine
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operated by the vapor of ether A Nobel, another Frenchman, in eighteen ninety
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four patented a machine for propelling torpedoes and other explosive missiles and for the controlling
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the course of balloons, the motive power of which is a gas developed in
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a closed reservoir by the chemical reaction of metallic sodium or potassium in a solution
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of ammonia. These vapor engines are used for vapor launches, bicycles, and
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automobiles. In eighteen fifty one, the ideas of Organs and Pappen of two
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hundred years before were revived by W. M. Storm, who in that
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year took out a gunpowder engine patent in the United States in which the air
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was compressed by the explosions of small charges of gunpowder. About fifteen other patterns
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have been taken out in America since that time for such engines, and some
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the engines are fed by cartridges which are exploded by pulling a trigger. As
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to gas and vapor engines generally, it may now be said, in comparison
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with steam, that although the steam engine is now regarded as almost perfect in
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operation, and that it can be started and stopped and otherwise controlled quietly,
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smoothly, instantaneously, and in the most uniform and satisfactory manner, yet there
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is the comparatively long delay in generating the steam and the boiler and the loss
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of heat and power as it is conducted in pipes to the working cylinder,
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resulting in the utilization of only ten percent of the actual power generated, whereas
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gas and vapor engines utilize twenty five percent of the power generated, and the
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flame and explosions are now as easily and noiselessly controlled as the flow of oil
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or water. The world is coming to agree with Professor Fleming Jenkins. The
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gas engines will ultimately supplant the steam, the smoke and sindri nuisance with them
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has been solved. The cister invention of the gas engine is the air engine.
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They can be no doubt about the success of this busy body, as
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it is now as swift and successful motor and a thousand different fields. Machines
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of which air, either hot or cold, is used in place of steam
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as the moving power to drive a piston or to be driven by a piston
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are known generally as air caloric or hot air engines, air compresses, or
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compressed air engines, and are also classed as pneumatic machines, air brakes,
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or pumps. They are now specifically known by the name of the purpose to
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which they are applied as air ship, ventilator, air brake, van blower,
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air pistol, airspring, et cetera. The attention of inventors was directed
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to its compressed and heated air as of motor as soon as steam became unknown
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an efficient servant but the most important. The only successful air machine existing prior
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to this century was the air pump, invented by Gueriki in sixteen fifty and
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subsequently perfected by Robert Boyle and others. The original pump in the Vagteburg hemispheres
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are still preserved. It is recorded that Amatons of France in sixteen ninety nine
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had an atmospheric fire wheel or air engine, in which a heated column of
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air was made to drive a wheel. It has already been noted that Pappened
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sixteen eighty to sixteen ninety proposed and did in steam. His last published work
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was a Latin essay upon a New system for raising water by the action of
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fire, published in seventeen o seven. The action of confined and compressed steam
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and gases and air is so nearly the same in the machines in which they
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constitute the Moulga power. Then the history develop a construction and operation of the
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machines of one class are closely interwoven with those of the others. Taking advantage
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of what had been taught them by Watt and others as to steam and steam
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engines, and of the principles and laws of gases. Is expounded by Boil
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Marriott duldin Aga Lasaque, that many of the gases, such as air,
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preserve a permanent expanse of gaseous form under all degrees of temperature, and a
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compression to which they had as yet been subjected. That when compressed and released,
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they will expand and exert a pressure in the contrary direction, until the
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gas and outside atmospheric pressure are in equilibrium. That this compressed gas pressure is
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equal and transmitted equally in all directions, And that the weight of a column
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of air resting on every horizontal square inch at the sea leg is very nearly
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fourteen point six pounds. The inventors of the nineteenth century were enabled by this
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supreme illumination to enter with confidence into that work of mechanical contrivances which has rendered
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the age so marvelous. It was natural that in the first development of mechanical
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appliances, they should be devoted to those pursuits of which men had the greatest
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practical interest. Thus, as to steam, it was first applied to the
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raising of water for mines, and then to road vehicles, and so in
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eighteen hundred Thomas Parkins of England invented and patented at hydrostatic engine or machine,
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whether purpose a drawing beer or other liquid out of a cellar or vault in
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a public house, which is likewise intended to be applied, or raising water
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out of mines, ships or wells, by the use of a sort of
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an air pump. He maintained in airport pructure on the bier in an air
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tight cask situated in the cellar, which was connected with pipes having air tight
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voalves with the upper floor. The liquif was forced from the cellar by the
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air pressure, and when turned off, the air pressure was resumed in the
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cask, which preserved the bier from being thrown into a state of flatness.
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Substantially, the same device in principle has been reinvented and incorporated in patents numerous
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times since, in the innumerable applications of the thematic machines and air tools of
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the century, especially of air compressing devices to the daily uses of life.
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We may, by turning first to our home, find its inner and outer
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walls painted by no matter of paint spraying machine, where such have been made
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that will coat forty six thousand square feet of surface in six hours. And
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it is said that paint can be thus applied not only more quickly, but
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more thoroughly and durably than by old process. The periodical and fascinating practice of
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house cleaning is now greatly facilitated by an air brush, having a pipe with
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a thin, wide end, in which are numerous perforations, and through which
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the air is foroiced by a little pump, and with which apparatus A far
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more efficient cleaning effect upon carpets, mattresses, curtains, clothes, and furniture
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can be obtained than by the time on a broom and duster. Is the
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home uncomfortable by reason of heat in summer insects, a compressor having tanks or
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cisterns in the cellar filled with cold or cool air, may be set to
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work to reduce the temperature of the house and fan the inmates with refreshing breeze.
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Air engines have been invented which can be used either heat or cool the
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air, or do one or the other automatically. The heating one wanted is
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by fuel in a furnace forced up by a working cylinder, and the cooling
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by the circulation of water. Runs small then copper tubes through which the air
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passes to the cylinder. To the charms of the distant church bell lead one
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to the house of worship. The worshiper goes with the comforting assurance at the
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chimes which send for such sweet harmonies. Are operated not by toiling, sweating
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bannock ropes, but by a musician who plays as upon an organ and works
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the keys, valves and stops by the aid of compressed air, and sometimes
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by the additional help of electricity. Mention has already been made of office and
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other elevators, and which compressed air is an important factor in operating the same
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and for preventing accidents. If a waterfall is convenient, air is compressed by
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the body of descending water and used to ventilate funnels and deep shafts and mines,
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or drive the drills or other tools. The pneumatic mail tube dispatched system
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by which letters, parcels, et cetera are sent for place to place by
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the force of atmospheric pressure in an air exhausted tube is a decidedly modern invention,
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unknown in use even by those who are still children. Tubes as large
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as eight inches in diameter are now in use in which cartridge boxes are placed,
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each holding six hundred or more letters, and when the air is exhausted,
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the cartridge is forced through the tubes to the distance, sometimes at three
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miles and more in a few minutes. And traveling by rail, the train
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is now guided in starting or in stopping on to the right track, which
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may be one of a forty or fifty, by a pneumatic switch. The
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switch is for the whole number of tracks being under the control of a single
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lafe operator. The fast moving train is stopped by an air brake, and
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the locomotive bell is rung by touching an air cylinder. The baggage smashing,
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a custom more honored in the Breach than in the Observance, is prevented by
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a nomadic baggage arrangement consisting of an air containing cylinder and an armor which to
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place the baggage, and which arm is then quickly raised by the cylinder biston
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and is automatically swung around by a cam action, carrying the baggage out of
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or into the car. Bridge building has been so facilitated by the use in
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the matter of machines for raising ey loads of stone and iron, and for
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riveting and hammering and other air tools, aided by the development of the art
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of quick transportation, that a firm of bridge builders in America can build a
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splendid bridge in Africa within a hundred days after the contract has been entered upon.
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Ship building is hastened by these same ear drilling and riveting machines. The
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propelling of cars, road vehicles, boats, balloons, and even ships by
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explosive gases and compressed air is an extensive art in itself, yet still in
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its infancy, and will be more fully described in the chapter in carrying machines.
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The realm of art has received a notable advancement by the use of a
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little blowpipe or atomizer, by which the pigments forming the background or beautiful bases
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are belong the trust that graduated force desired by the operator to produce the most
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exquisitely smooth and blunded effects, while the varying colors are made to melt imperceptibly
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into one another, as delicately as the mingled shade in colored sunlight falls on
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a forest brook. But to enumerate the industrial arts to which air and other
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nomadic machines have been adapted would be to catalog them. All. Mention is
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made of others in chapters in which those special arts are treated, and of Section thirteen