the invention complete, but Watt saw clearly that years of unceasing labor might yet pass before the details could all be worked out and the steam engine appear ready to revolutionise the labor of the world. During these years, Professor Black was his chief adviser and encouraged him in hours of disappointment. The true and able friend not only did this, but furnished him with money needed to enable him to concentrate all his time and strength upon the task.

Most opportunely, at this juncture, came Watt's marriage, to his cousin Miss Miller, a lady to whom he had long been deeply attached. Watt's friends are agreed in stating that the marriage was of vast importance, for he had not passed untouched through the days of toil and trial. Always of a meditative turn, somewhat prone to melancholy when without companionship, and withal a sufferer from nervous headaches, there was probably no gift of the gods equal to that of such a wife as he had been so fortunate as to secure. Gentle yet strong in her gentleness, it was her courage, her faith, and her smile that kept Watt steadfast. No doubt he, like many other men blessed with an angel in the household, could truly aver that his worrying cares vanished at the doorstep.

Watt had at last, what he never had before, a home. More than one intimate friend has given expression to the doubt whether he could have triumphed without Mrs. Watt's bright and cheerful temperament to keep

him from despondency during the trying years which he had now to encounter. Says Miss Campbell:

I have not entered into any of the interesting details my mother gave me of Mr. Watt's early and constant attachment to his cousin Miss Miller; but she ever considered it as having added to his enjoyment of life, and as having had the most beneficial influence on his character. Even his powerful mind sank occasionally into misanthropic gloom, from the pressure of long-continued nervous headaches, and repeated disappointments in his hopes of success in life. Mrs. Watt, from her sweetness of temper, and lively, cheerful disposition, had power to win him from every wayward fancy; to rouse and animate him to active exertion. She drew out all his gentle virtues, his native benevolence and warm affections.

From all that has been recorded of her, we are justified in classing Watt with Bassanio.

"It is very meet

He live an upright life,

For having such a blessing in his lady,

He finds the joys of heaven here on earth;

And if on earth he do not merit it,

In reason he should never come to heaven."

Watt knew and felt this and let us hope that, as was his duty, he let Mrs. Watt know it, not only by act, but by frequent acknowledgment.

Watt did not marry imprudently, for his instrumentmaking business had increased, as was to have been expected, for his work soon made a reputation as being most perfectly executed. At first he was able to carry out all his orders himself; now he had as

many as sixteen workmen. He took a Mr. Craig as a partner, to obtain needed capital. His profits one year were $3,000. The business had been removed in 1760 to new quarters in the city, and Watt himself had rented a house outside the university grounds. Having furnished it, Watt brought his young wife and installed her there, July, 1764. We leave him there, happy in the knowledge that he is to be carefully looked after, and, last but not least, steadily encouraged and counselled not to give up the engine. shall presently see, such encouragement was much needed at intervals.

As we

The first step was to construct a model embodying all the inventions in a working form. An old cellar was rented, and there the work began. To prepare the plan was easy, but its execution was quite another story. Watt's sad experience with indifferent work had not been lost upon him, and he was determined that, come what may, this working model should not fail from imperfect construction. His own handiwork had been of the finest and most delicate kind, but, as he said, he had "very little experience of mechanics "in great." This model was a monster in those days, and great was the difficulty of finding mechanics capable of carrying out his designs. The only available men were blacksmiths and tinsmiths, and these were most clumsy workmen, even in their own crafts. Were Watt to revisit the earth to-day, he would not easily

find a more decided change or advance over 1764, in all that has been changed or improved since then, than in this very department of applied mechanics. To-day such a model as Watt constructed in the cellar would be simple work indeed. Even the gasoline or the electric motor of to-day, though complicated far beyond the steam model, is now produced by automatic machinery. Skilled workmen do not have to fashion the parts. They only stand looking on at machinery-itself made by automatic tools-performing work of unerring accuracy. Had Watt had at his call only a small part of the inventor's resources of our day, his model steam engine might have been named the Minerva, for Minerva-like, it would have sprung forth complete, the creature of automatic machinery, the workmen meanwhile smilingly looking on at these slaves of the me chanic which had been brought forth and harnessed to do his bidding by the exercise of godlike reason.

The model was ready after six months of unceasing labor, but notwithstanding the scrupulous fastidiousness displayed by Watt in the workmanship of all the parts, the machine, alas, “snifted at many openings." Little can our mechanics of to-day estimate what "perfect joints" meant in those days. The entire correctness of the great idea was, however, demonstrated by the trials made. The right principle had been discovered; no doubt of that. Watt's decision was that "it must be followed to an issue." There was no peace

for him otherwise. He wrote (April, 1765) to a friend, "My whole thoughts are bent on this machine. I can "think of nothing else." Of course not; he was hot in the chase of the biggest game hunter ever had laid eyes on. He had seen it, and he knew he had the weapons to bring it down. A larger model, free as possible from defects which he felt he could avoid in the next, was promptly determined upon. A larger and better shop was obtained, and here Watt shut himself up with an assistant and erected the second model. Two months sufficed, instead of six required for the first. This one also at first trial leaked in many directions, and the condenser needed alterations. Nevertheless, the engine accomplished much, for it worked readily with ten and one-half pounds pressure per square inch, a decided increase over previous results. It was still the cylinder and its piston that gave Watt the chief trouble. No wonder the cylinder leaked. It had to be hammered into something like true lines, for at that day so backward was the art that not even the whole collective mechanical skill of cylinder-making could furnish a bored cylinder of the simplest kind. This is not to be construed as unduly hard upon Glasgow, for it is said that all the skill of the world could not do so in 1765, only one hundred and forty years ago. We travel so fast that it is not surprising that there are wiseacres among us quite convinced that we are standing still.

We may be pardoned for again emphasising the fact