Chinese ,Eo colipilc was applied to new uses at Pekin in 1694. Two experiments were made with it before the emperor Cans Hi. In the middle of a wagon about two feet long was placed a brazen vessel full of live coals, and upon them an Tuolipile, the wind of which came through a little pipe upon a sort of wheel made like the sails of a wind mill; this wheel turned another, and by that means set the wagon in motion for hours together. This wagon was furnished with mechanical devices by which it could he turned around in any given circle. The same contrivance was likewise fixed to a little ship with four wheels. The molipile was hidden in the middle of the ship, and the wind from two small pipes filled the sails and made it wheel about a long while.
Sovely' s first successful experiment with the steam-engine, or " fire-engine," as it was then called, was by Thomas Savory, who in [698 obtained a patent the title of which reads, "A grant to Thomas Savery, Gentl., of the sole exercise of a new invention by him invented, for raising of water, and occasioning motion to all sorts of mill works, by the impellant force of fire, which will be of great use for drain ing mines, serving towns with water, and for working of all sorts of mills when they have not the benefit of water nor constant winds." This machine, which was applied to raising water from the deep mines of Great Britain, was an adaptation of Worcester's " fire-engine." It required for what we know as a "horse-power" (that is, the equivalent of 33,00o pounds lifted one foot high in a minute, or 55o pounds lifted one foot high in a sec ond) the combustion of thirty pounds of coal. Savory's device possessed neither cylinder, piston, crank, nor fly-wheel—in fact, no moving parts. The model of his machine (pr. So, AT. 6), a description of which he presented to the Royal Society, consisted of a furnace (A) heating a boiler (13), which was connected by pipes (C, C) with two copper receivers (D, D). From the bottoms of these receivers were led branch-pipes (F, F) turned upward., which were united to form a " forcing-pipe" (C); from the top of each receiver was led a pipe turned downward, and these two pipes united formed a supply-pipe which extended to the bottom of the well from which the water was to be drawn. Steam being generated in the boiler B, and the cock C being opened, the receiver D is filled with steam. Closing the cock condenses the steam in the receiver, in which a vacuum is created, and the pressure of the atmosphere forces the water up through the supply-pipe from the well into the receiver. Opening again the cock C, the check-valve in the suction-pipe at E closes; the steam drives the water out through the forcing-pipe G, the clack-valve E on that pipe opening before it. The valve C is again closed, the steam again condenses,
and the operation is repeated. While one of the two receivers is discharg ing; the other is filling, and thus the steam is drawn from the boiler with tolerable regularity, and the expulsion of water takes place with similar uniformity, the two systems of receivers and pipes being worked alter nately by the single boiler. A modification of this employed surface-con densation to hasten the work. Desaguliers, in 1718, substituted jet- for surface-condensation. Blakely, in 1766, interposed a cushion of oil between the water in the reservoirs and the steam which drove it out.
Savery's engine, which was subsequently much improved, was exten sively employed in pumping out mines, and was occasionally used in raising water to supply houses in towns and for driving mill-wheels. Though it was entirely displaced by Newcomen's engine, its inventor must be awarded the credit of having first practically employed the steam-boiler, without which Newcomen and Cawley could not have set their more advantageously acting machine in motion. The piston moving in a cyl inder was proposed by Huygens in 1680.
Papin's Steanz-engine.—Den is Papin, a humble French physicist, en deavored in 1688 to improve Huygens' apparatus, but having unsuccess fully tried gunpowder, he proposed in r69o, while professor at Marburg, the substitution of steam for producing a vacuum under the piston. Papin's engine (pl. So, fig. 7) was constructed practically on the same principle as Huygens'. Instead of gunpowder a small quantity of water was introduced into the cylinder through an opening in the piston, and the opening was then closed by means of the rod A fire being started beneath the cyl inder, whose bottom was of very thin metal, steam was rapidly generated, and by its elastic force overcame the weight of the piston B and the sure of the atmosphere, and drove the piston to the top of the cylin der, where a latch E, engaging a notch in the piston-rod, and kept in contact with the latter by a spring, held it up. On removing the fire, there followed a condensation of the steam, by which a vacuum was pro duced below the piston, and, upon disengaging the latch, the piston, being forced down by atmospheric pressure, raised the weight attached to the rope L passing over the pulleys T,T. The cylinder had a diameter of two and a half inches. Papin's was the earliest cylinder-and-piston steam-engine, but he was not successful in perfecting his apparatus, though he devised various transmitting mechanisms for the motion of the piston, especially for propelling a vessel.