ted Watt to visit him with the Professor at his
country home, and urged him to press forward his invention "whether he
pursued it as a philosopher or as a man of business." In the month of
November Watt sent Roebuck drawings of a covered cylinder and piston to
be cast at his works, but it was so poorly done as to be useless. "My
principal difficulty in making engines," he wrote Roebuck, "is always
the smith-work."

By this time, Watt was seriously embarrassed for money. Experiments cost
much and brought in nothing. His duty to his family required that he
should abandon these for a time and labor for means to support it. He
determined to begin as a surveyor, as he had mastered the art when
making surveying instruments, as was his custom to study and master
wherever he touched. He could never rest until he knew all there was to
know about anything. Of course he succeeded. Everybody knew he would,
and therefore business came to him. Even a public body, the magistrates
of Glasgow, had not the slightest hesitation in obtaining his services
to survey a canal which was to open a new coal field. He was also
commissioned to survey the proposed Forth and Clyde canal. Had he been
content to earn money and become leading surveyor or engineer of
Britain, the world might have waited long for the forthcoming giant
destined to do the world's work; but there was little danger of this.
The world had not a temptation that could draw Watt from his appointed
work. His thoughts were ever with his engine, every spare moment being
devoted to it. Roebuck's speculative and enterprising nature led him
also into the entrancing field of steam. It haunted him until finally,
in 1767, he decided to pay off Watt's debts to the amount of a thousand
pounds, provide means for further experiments, and secure a patent for
the engine. In return, he became owner of two thirds of the invention.

Next year Watt made trial of a new and larger model, with unsatisfactory
results upon the first trial. He wrote Roebuck that "by an unforeseen
misfortune, the mercury found its way into the cylinder and played the
devil with the solder." Only after a month's hard labor was the second
trial made, with very different and indeed astonishing results--"success
to my heart's content," exclaimed Watt. Now he would pay his
long-promised debt to his partner Roebuck, to whom he wrote, "I
sincerely wish you joy of this successful result, and hope it will make
some return for the