The most powerful and important mass of matter on the earth is the steam engine. It is the throbbing heart of civilization, even as the printing press is its brain. It would be difficult for man to compute his debt to steam. Upon it he relies for food, clothing, and shelter, the three necessities for which the race has always striven; and without it he could have scarcely any of life's comforts and luxuries. Steam is the mistress of commerce, manufacturing, and mining, and the servant of agriculture. Steam gives employment to millions of men. It plants cities and towns in waste places. It enables man to leave the little valley or hillside where his fathers lived, and makes of him a citizen of the world. It lessens the power of time and space, and makes neighbors of ocean-divided continents.

It would not be easy for men living in the twentieth century to imagine a society uninfluenced by the use of steam; but nearly all of man's life on the earth has been passed without its help. Fire and water, the two productive factors of steam, have always existed; but it was not until a few score of years ago that man learned to put them together successfully, and to produce the greatest force known to civilization. In the few years since its discovery it has spread to every nook and corner of civilization. Suppose you could ascend to some great height whence you could see working at one time all the steam driven machinery in the world. What a sight it would be! What if the noise from all this machinery—the screech of the speeding locomotive, the hum and roar of factory and mill, the hoarse yell of ships, and the puffing of mine-engines—should reach your ear at once? What a sound it would be!

The idea of using steam for driving stationary machinery originated in the early centuries. This was the first use to which steam was put. For a long time no one seems to have thought of using it for transportation purposes. As far back as 130 B.C., we find mention of "heat engines," which employed steam as their motive power, and were used for organ blowing, the turning of spits, and like purposes. But from this early date till the seventeenth century practically no progress was made in the use of steam. Though men had experimented with steam up to this time with more or less success, the world is chiefly indebted for the developed type of the steam engine to James Watt and George Stephenson.

Watt was born in Greenock, Scotland, January 19, 1736. He was a poor boy and early in life he was thrown upon his own resources. During his youth he struggled against ill health; for days at a time he was prostrated with severe headaches. But he was bright, determined, and had a genial disposition that made him many friends. When he was twenty-one years old, he secured a position as maker of scientific instruments for the university in Glasgow. He began discussing with some scientific friends at the university the possibility of improving the steam engine, which at that time was used only for pumping water, chiefly in the drainage of mines. He entered upon a scientific study of the properties of steam and tried to devise means for making the steam engine more useful. One Sunday afternoon early in 1765, while walking in Glasgow, the idea he had studied so long to evolve suddenly flashed into his mind. Without delay Watt put his plan to the test and found that it worked.

For a long time, owing to a lack of money, he had difficulty in establishing the merits of his improvements. Finally he formed a partnership with Matthew Boulton, a wealthy and energetic man who lived at Birmingham, England. They began the manufacture of steam engines at Birmingham, under the firm name of Boulton and Watt. This partnership was very successful. Watt supplied the inventions; Boulton furnished the money and attended to the business.

Before the time of Watt, the steam engine was exclusively a steam pump—slow, cumbrous, wasteful of fuel, and very little used. Watt made it a quick, powerful, and efficient engine, requiring only a fourth as much fuel as before. Under his first patent the engine was still used only as a steam pump; but his later improvements adapted it for driving stationary machinery of all kinds and, save in a few respects, left it essentially what it is to-day. Prior to Watt's inventions, the mines of Great Britain were far from thriving. Many were even on the point of being abandoned, through the difficulty of removing the large quantities of water that collected in them. His improvements made it possible to remove this water at a moderate cost, and this gave many of the mines a new lease of life. The commercial success of his engine was soon fully established.

Watt paid practically no attention to the use of steam for purposes of transportation. In one of his patents he described a steam locomotive; but he offered little encouragement when his chief assistant, Murdoch, who was the inventor of gas lighting, made experiments with steam for locomotion. The notion then was to use a steam carriage on ordinary roads. Railroads had not been thought of. When the idea of using steam on railways began to take shape in the later days of Watt, he refused to encourage the plan. It is said that he even put a clause in a lease of his house, providing that no steam carriage should ever approach it under any pretext whatever.

Besides developing the steam engine, Watt made other inventions, including a press for copying letters. He also probably discovered the chemical composition of water. He died at Heathfield, England, on the nineteenth of August, 1819.

It is denied many men to see the magnitude of their achievements. Moses