bject in August, 1787, and constructed some lamps which
proved great successes.

The following year he invented an instrument for determining the
specific gravities of liquids, which was generally adopted.

One of Watt's inventions was a new method of readily measuring distances
by telescope, which he used in making his various surveys for canals.
Such instruments are in general use to-day. Brough's treatise on
"Mining" (10th ed., p. 228) gives a very complete account of them, and
states that "the original instrument of this class is that invented by
James Watt in 1771."

In his leisure hours, Watt invented an ingenious machine for drawing in
perspective, using the double parallel ruler, then very little known and
not at all used as far as Watt knew. Watt reports having made from fifty
to eighty of these machines, which went to various parts of the world.

In 1810 Watt informs Berthollet that for several years he had felt
unable, owing to the state of his health, to make chemical experiments.
But idle he could not be; he must be at work upon something. As he often
said, "without a hobby-horse, what is life?" So the saying is reported,
but we may conclude that the "horse" is here an interpolation, for the
difference between "a horse" and "a hobby" is radical--a man can get off
a horse.

Watt's next "hobby" fortunately became an engrossing occupation and kept
him alert. This was a machine for copying sculpture. A machine he had
seen in Paris for tracing and multiplying the dies of medals, suggested
the other. After much labor and many experiments he did get some measure
of success, and made a large head of Locke in yellow wood, and a small
head of his friend Adam Smith.

Long did Watt toil at the new hobby in the garret where it had been
created, but the garret proved too hot in summer and too cold in
winter. March 14, 1810, he writes Berthollet and Leveque:

I still do a little in mechanics: a part of which, if I live to
complete it, I shall have the honor of communicating to my
friends in France.

He went steadily forward and succeeded in making some fine copies in
1814. For one of Sappho he gives dates and the hours required for
various parts, making a total of thirty-nine. Some censorious
Sabbatarians discovered that the day he was employed one hour "doing her
breast with 1/8th drill" was Sabbath, which in one who belonged to a
strict Scottish Covenanter family, betokened a sad fall from grace. Wh