day. In July of that year he writes Dr. Black that he has "lately discovered a method of copying writing "instantaneously, provided it has been written within

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twenty-four hours. I send you a specimen and will "impart the secret if it will be of any use to you. It "enables me to copy all my business letters." He kept this secret for two years, and in May, 1780, secured a patent after he had completed details of the press and experimented with the ink. One hundred and fifty were made and sold. Thirty of these went abroad. It steadily made its way. later, said it had proved so useful to him that it was well worth all the trouble of perfecting it, even if it brought no profit.

Watt, writing some thirty years

We think of Watt and the steam engine appears. Let us however note the unobtrusive little copyingpress on the table at his side. Extremes meet here. It would be difficult to name an invention more universally used, in all offices where man labors in any field of activity. In the list of modest inventions of greatest usefulness, the modern copying-press must take high rank, and this we owe entirely to Watt.

Of the same period as the copying-machine is his invention of a drying-machine for cloth, consisting of three cylinders of copper over which the cloth must turn over and under while cylinders are filled with steam, the cloth to be alternately wound off and on the two wooden rollers, by which means it will pass over three

cylinders in succession. This machine was erected for Watt's father-in-law, Mr. MacGregor in Glasgow, by an ingenious mechanic, John Gardiner, often employed by Watt in earlier years. "This I apprehend," he writes to David Brewster in 1814, "to be the original from "which such machines were made." When we consider the extent to which such steam drying-machines are used in our day, our estimate of the credit due to Watt cannot be small. The drying-machine is no unfit companion to the copying-machine.

Watt revisited Cornwall in 1781 to make an inspection of all the engines. Much he found needing attention and improvement. His evenings were spent designing "road steam-carriages." This was before the day of railroads, and the carriages were to be driven by steam over the ordinary coach roads. He filled a quarto drawing-book with different plans for these, and covered the idea in one of his patent specifications. Boulton suggested in 1781 that the idea of rotary motion should be developed, which Watt had from the first regarded as of prime importance. It was for this he had invented his original wheel engine, and in his first patent of 1769 he describes one method of securing it. It occurred to him that the ordinary engine might be adapted to give the rotary motion. He wrote from Cornwall to Boulton: "As to the circular motion, I will apply it as soon as I can." He prepared a model upon his return to Soho, using

a crank connected with the working-beam of the engine for that purpose, which worked satisfactorily. There was nothing new in the crank motion; it was used on every spinning-wheel, grind-stone and foot-lathe turned by hand, but its application to the steam-engine was As early as 1771, he writes:

new.

I have at times had my thoughts a good deal upon the subject. In general, it appears to me that a crank of a sufficient sweep will be by much the sweetest motion, and perhaps not the dearest, if its durability be considered. . . . I then resolved to adopt the crank. Of this I caused a model to be made, which performed to satisfaction. But being then very much engaged with other business, I neglected to take a patent immediately, and having employed a blackguard of the name of Cartwright (who was afterward hanged), about this model, he, when in company with some of the same sort who worked at Wasborough's mill, and were complaining of its irregularities and frequent disasters,' told them he could put them in a way to make a rotative motion which would not go out of order nor stun them with its noise, and accordingly explained to them what he had seen me do. Soon after (which, John Steed, who was engineer at Wasborough's mill, took a patent for a rotative motion with a crank, and applied it to their engine. Suspicions arising of Cartwright's treachery, he was strictly questioned, and confessed his part in the transaction when too late to be of service to us.

Overtures were made by Wasborough to exchange patents and work together, which Watt scornfully rejected. He writes:

Though I am not so saucy as many of my countrymen, I have enough innate pride to prevent me from doing a mean action because a servile prudence may dictate it. . . . I will never meanly sue a thief to give me my own again unless I have nothing left behind.

His blood was up. No dealings with rascals!

July, 1781, Watt had finished his studies, went to Penryn, and swore he had "invented certain new methods of applying the vibrating or reciprocating "motion of steam or fire engines to produce a continued "rotation or circular motion round an axis or centre, "and thereby to give motion to the wheels of mills or "other machines."

Watt proceeded to work out the plan of the rotary engine, stimulated by numerous inquiries for steam engines for driving all kinds of mills. He found that "the people in London, Manchester and Birmingham "are steam-mill mad."

During many long years of trial with their financial troubles, inferior and drunken workmen, disappointing engines, Cornish mine-owners to annoy him, it is highly probable that Watt only found relief in retiring to his garret to gratify his passion for solving difficult mechanical problems. We may even imagine that from his serious mission-the development of the enginewhich was ever present, he sometimes flew to the numerous less exhausting inventions for recreation, as the weary student flies to fiction. His mind at this period seems never to have been at rest. His voluminous correspondence constantly reveals one invention after another upon which he was engaged. A new micrometer, a dividing screw, a new surveyingquadrant, problems for clearing the observed distance

of the moon from a star of the effects of refraction and parallax, a drawing-machine, a copying-machine for sculpture-anything and everything he used or saw seems immediately to have been subjected to the question: "Cannot this be improved?" usually with a response in the affirmative.

As we have read, he had long studied the question of a locomotive steam carriage. In Muirhead's Biography, several pages are devoted to this. In his seventh "new improvement," in his patent of 1784, he describes "the principle and construction of steam "engines which are applied to give motion to wheel "carriages for removing persons, goods, or other

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matter from place to place, in which case the engines "themselves must be portable.' Mr. Murdoch made a model of the engine here specified which performed well, but nothing important came of all this until 1802, when the problem was instantly changed by Watt's friend, Mr. Edgeworth, writing him, “I have "always thought that steam would become the universal "lord, and that we should in time scorn post-horses. "An iron railroad would be a cheaper thing than a road of the common construction." Here lay in a few words the idea from which our railway system has sprung. Surely Edgeworth deserves to be placed among the immortals. As in the case of the steamship, however,

*Since the above was put in type I learn that in his forthcoming book upon "The Development of the Locomotive," which promises to become the standard, Mr. Angus Sinclair says: "The first suggestion of a railroad for goods transportation