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vanes of a small wheel to run it, and told how in other ways Hero's engine might be employed for useful purposes.

The first English publication describing a way of applying steam appeared in 1630 in a patent granted to David Ramseye, for a mode of raising water thereby. This was followed by patents to Grant in 1632 and to one Ford in 1640. During that century these crude machines were called "fire engines." It seems to have been common in some parts of Europe during the seventeenth century to use a blast of steam to improve the draft of chimneys and of blast furnaces. This application of steam to smoke and smelting has been frequently revived by modern inventors with much flourish of originality.

It is with a certain feeling of delight and relief, after a prolonged search through the centuries for some evidence of harnessing this mighty agent to man's use, that we come to the efforts of the good Marquis of Worcester-Edward Somerset. He it was who in 1655 wrote of the Inventions of the Sixteenth Century. He afterwards amplified this title by calling his book A Century of Names and Scantlings of such Inventions as at present I call to mind to have tried and perfected, etc.

There are about one hundred of these "Scantlings," and his descriptions of them are very brief but interesting. Some, if revived now and put to use, would throw proposed flying machines into the background, as they involved perpetual motion.

But to his honor be it said that he was the first steam-engine builder. A patent was issued to him in 1663. It was about 1668 that he built and put in successful operation at Raglan Castle at Vauxhall, near London, a steam engine to force water upward.

He made separate boilers, which he worked alternately, and conveyed the steam from them to a vessel in which its pressure operated to force the water up. Unfortunately he did not leave a description of his inventions sufficiently full to enable later mechanics to make and use them. He strove in vain to get capital interested and a company formed to manufacture his engines. The age of fear and speculation as to steam ceased when the Marquis set his engine to pumping water, and from that time inventors went on to put the arm of steam to work.

In 1683 Sir Samuel Morland commenced the construction of the Worcester engines for use and sale; Hautefeuille of France taught the use of gas, described how gas as well as steam engines might be constructed, and was the first to propose the use of the piston. The learned writings of the great Dutch scientist and inventor, Huygens, on heat and light steam and gas, also then came forth, and his assistant, the French physicist and doctor, Denis Papin, in 1690, proposed steam as a universal motive power, invented a steam engine having a piston and a safety valve, and even a crude paddle steamer, which it is said was tried in 1707 on the river Fulda. Then in 1698 came Thomas Savery, who patented a steam engine that was used in draining mines.

The eighteenth century thus commenced with a practical knowledge of the power of steam and of means for controlling and working it.

Then followed the combined invention of Newcomen, Cawley and Savery, in 1705, of the most successful pumping engine up to that time. In this engine a cylinder was employed for receiving the steam from a separate boiler. There was a piston in the cylinder driven up by the steam admitted below

it, aided by a counterpoise at one end of an engine beam. The steam was then cut off from the boiler and condensed by the introduction beneath the piston of a jet of water, and the condensed steam and water drawn off by a pipe. Atmospheric pressure forced the piston down. The piston and pump rods were connected to the opposite ends of a working beam of a pumping engine, as in some modern engines. Gauge cocks to indicate the height of water, and a safety valve to regulate the pressure of steam, were employed. Then came the ingenious improvement of the boy Humphrey Potter, connecting the valve gear with the engine beam by cords, so as to do automatically what he was set to do by hand, and the improvement on that of the Beighton plug rod. Still further improved by others, the Newcomen engine came into use through out Europe.

Jonathan Hulls patented in England in 1736 a marine steam engine, and in 1737 published a description of a Newcomen engine applied to his system for towing ships. William Henry, of Pennsylvania, tried a model steamboat on the Conestoga river in 1763.

This was practically the state of the art, in 1763, when James Watt entered the field. His brilliant inventions harnessed steam to more than pumping engines, made it a universal servant in manifold industries, and started it on a career which has revolutionized the trade and manufactures of the world.

To understand what the nineteenth century has done in steam motive power we must first know what Watt did in the eighteenth century, as he then laid the foundation on which the later inventions have all been built.

Taking up the crude but successful working en

gine of Newcomen, a model of which had been sent to him for repairs, he began an exhaustive study of the properties of steam and of the means for producing and controlling it. He found it necessary to devise a new system.

Watt saw that the alternate heating and cooling of the cylinder made the engine work slowly and caused an excessive consumption of steam. He concluded that "the cylinder should always be as hot as the steam that entered it." He therefore closed the cylinder and provided a separate condensing vessel into which the steam was led after it raised the piston. He provided an air-tight jacket for the cylinder, to maintain its heat. He added a tight packing in the cylinder-head for the piston-rod to move through, and a steam-tight stuffing-box on the top of the cylinder. He caused the steam to alternately enter below and above the piston and be alternately condensed to drive the piston down as well as up, and this made the engine double-acting, increasing its power and speed. He converted the reciprocating motion of the piston into a rotary motion by the adoption of the crank, and introduced the well-known parallel motion, and many other improvements. In short, he demonstrated for the first time by a practical and efficient engine that the expansive force of steam could be used to drive all ordinary machinery. He then secured his inventions by patents against piracy, and sustained them successfully in many a hard-fought battle. It had taken him the last quarter of the 18th century to do all these things.

Watt was the proper precursor of the nineteenth century inventions, as in him were combined the power and attainments of a great scientist and the genius of a great mechanic. The last eighteen years

of his life were passed in the 19th century, and he was thus enabled to see his inventions brought within its threshold and applied to those arts which have made this age so glorious in mechanical achievements.

Watt so fitly represents the class of modern great inventors in his character and attainments that the description of him by Sir Walter Scott is here pertinent as a tribute to that class, and as a delineation of the general character of those benefactors of his race of which he was so conspicuous an example:Says Sir Walter:

"Amidst this company stood Mr. Watt, the man whose genius discovered the means of multiplying our national resources to a degree, perhaps, even beyond his own stupendous powers of calculation and combination; bringing the treasures of the abyss to the summit of the earth-giving to the feeble arm of man the momentum of an Afrite commanding manufactures to rise-affording means of dispensing with that time and tide which wait for no man-and of sailing without that wind which defied the commands and threats of Xerxes himself. This potent commander of the elements-this abridger of time and space this magician, whose cloudy machinery has produced a change in the world, the effects of which, extraordinary as they are, are perhaps only beginning to be felt-was not only the most profound man of science, the most successful combiner of powers and calculator of numbers, as adapted to practical purposes, was not only one of the most generally wellinformed, but one of the best and kindest of human beings."

The first practical application of steam as a work

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