fford. His duty to provide for the frugal wants of his family became
imperative. "I had," he said, "a wife and children, and I saw myself
growing gray without having any settled way of providing for them." He
turned again to surveying and prospered, for few such men as Watt were
to be found in those days, or in any day. With a record of Watt's work
as surveyor, engineer, councillor, etc., our readers need not be
troubled in detail. It should, however, be recorded that the chief canal
schemes in Scotland in this, the day of canals for internal commerce,
preceding the day of railroads that was to come, were entrusted to Watt,
who continued to act as engineer for the Monkland Canal. While Watt was
acting as engineer for this (1770-72), Dr. Small wrote him that he and
Boulton had been talking of moving canal boats by the steam engine on
the high-pressure principle. In his reply, September 30, 1770, Watt
asks, "Have you ever considered a spiral oar for that purpose, or are
you for two wheels?" To make his meaning quite plain, he gives a rough
sketch of the screw propeller, with four turns as used to-day.

Thus the idea of the screw propeller to be worked by his own improved
engine was propounded by Watt one hundred and thirty-five years ago.

This is a remarkable letter, and a still more remarkable sketch, and
adds another to the many true forecasts of future development made by
this teeming brain.

Watt also made a survey of the Clyde, and reported upon its proposed
deepening. His suggestions remained unacted upon for several years, when
the work was begun, and is not ended even in our day, of making a trout
and salmon stream into one of the busiest, navigable highways of the
world. This year further improvements have been decided upon, so that
the monsters of our day, with 16,000-horse-power turbine engines, may be
built near Glasgow. Watt also made surveys for a canal between Perth and
Coupar Angus, for the well-known Crinan Canal and other projects in the
Western Highlands, as also for the great Caledonian and the Forth and
Clyde Canals.

The Perth Canal was forty miles long through a rough country, and took
forty-three days, for which Watt's fee, including expenses, was $400.
Labor, even of the highest kind, was cheap in those times. We note his
getting thirty-seven dollars for plans of a bridge over the Clyde. Watt
prepared plans for docks and piers at Port Glasgow and for a new harbor
at Ayr. His last and most impo