has been a most sincere and generous friend," said Watt, "and
is a truly worthy man." And again, "My heart bleeds for him, but I can
do nothing to help him: I have stuck by him till I have much hurt
myself; I can do so no longer; my family calls for my care to provide
for them." The later years of Dr. Roebuck's life were spent in
comparative obscurity; and he died in 1794, in his 76th year.

He lived to witness the success of the steam-engine, the opening up of
the Boroughstoness coal,[4] and the rapid extension of the Scotch iron
trade, though he shared in the prosperity of neither of those branches
of industry. He had been working ahead of his age, and he suffered for
it. He fell in the breach at the critical moment, and more fortunate
men marched over his body into the fortress which his enterprise and
valour had mainly contributed to win. Before his great undertaking of
the Carron Works, Scotland was entirely dependent upon other countries
for its supply of iron. In 1760, the first year of its operations, the
whole produce was 1500 tons. In course of time other iron works were
erected, at Clyde Cleugh, Muirkirk, and Devon--the managers and
overseers of which, as well as the workmen, had mostly received their
training and experience at Carron--until at length the iron trade of
Scotland has assumed such a magnitude that its manufacturers are
enabled to export to England and other countries upwards of 500,000
tons a-year. How different this state of things from the time when
raids were made across the Border for the purpose of obtaining a store
of iron plunder to be carried back into Scotland!

The extraordinary expansion of the Scotch iron trade of late years has
been mainly due to the discovery by David Mushet of the Black Band
ironstone in 1801, and the invention of the Hot Blast by James Beaumont
Neilson in 1828. David Mushet was born at Dalkeith, near Edinburgh, in
1772.[5] Like other members of his family he was brought up to
metal-founding. At the age of nineteen he joined the staff of the
Clyde Iron Works, near Glasgow, at a time when the Company had only two
blast-furnaces at work. The office of accountant, which he held,
precluded him from taking any part in the manufacturing operations of
the concern. But being of a speculative and ingenious turn of mind,
the remarkable conversions which iron underwent in the process of
manufacture very shortly began to occupy his attention. The subject
was