cient; and
when Dr. Roebuck's friend, Professor Black, of Edinburgh, informed him
of a young man of his acquaintance, a mathematical instrument maker at
Glasgow, having invented a steam-engine calculated to work with
increased power, speed, and economy, compared with Newcomen's; Dr.
Roebuck was much interested, and shortly after entered into a
correspondence with James Watt, the mathematical instrument maker
aforesaid on the subject. The Doctor urged that Watt, who, up to that
time, had confined himself to models, should come over to Kinneil
House, and proceed to erect a working; engine in one of the
outbuildings. The English workmen whom he had brought; to the Carron
works would, he justly thought, give Watt a better chance of success
with his engine than if made by the clumsy whitesmiths and blacksmiths
of Glasgow, quite unaccustomed as they were to first-class work; and he
proposed himself to cast the cylinders at Carron previous to Watt's
intended visit to him at Kinneil.

Watt paid his promised visit in May, 1768, and Roebuck was by this time
so much interested in the invention, that the subject of his becoming a
partner with Watt, with the object of introducing the engine into
general use, was seriously discussed. Watt had been labouring at his
invention for several years, contending with many difficulties, but
especially with the main difficulty of limited means. He had borrowed
considerable sums of money from Dr. Black to enable him to prosecute
his experiments, and he felt the debt to hang like a millstone round
his neck. Watt was a sickly, fragile man, and a constant sufferer from
violent headaches; besides he was by nature timid, desponding,
painfully anxious, and easily cast down by failure. Indeed, he was
more than once on the point of abandoning his invention in despair. On
the other hand, Dr. Roebuck was accustomed to great enterprises, a bold
and undaunted man, and disregardful of expense where he saw before him
a reasonable prospect of success. His reputation as a practical
chemist and philosopher, and his success as the founder of the
Prestonpans Chemical Works and of the Carron Iron Works, justified the
friends of Watt in thinking that he was of all men the best calculated
to help him at this juncture, and hence they sought to bring about a
more intimate connection between the two. The result was that Dr.
Roebuck eventually became a partner to the extent of two-thirds of the
invention, took