efore Hargreaves obtained his patent for the spinning-jenny.
These are the two inventors, with Whitney, the American inventor of the
cotton-gin, from whose brains came the development of the textile
industry in which Britain still stands foremost. Fifty-six millions of
spindles turn to-day in the little island--more than all the rest of the
civilised world can boast. Much later came Stephenson with his
locomotive. Here is a record for a quartette of manual laborers in the
truest sense, actual wage-earners as mechanics--Watt, Stephenson,
Arkwright, and Hargreaves! Where is that quartette to be equalled?

Workingmen of our day should ponder over this, and take to heart the
truth that manual mechanical labor is the likeliest career to develop
mechanical inventors and lead them to such distinction as these
benefactors of man achieved. If disposed to mourn the lack of
opportunity, they should think of these working-men, whose advantages
were small compared to those of our day.

The greatest invention of all, the condenser, is fully covered by the
first patent of 1769. The best engine up to this time was the Newcomen,
exclusively used for pumping water. As we have seen, it was an
atmospheric engine, in no sense a steam engine. Steam was only used to
force the heavy piston upward, no other work being done by it. All the
pumping was done on the downward stroke. The condensation of the spent
steam below the piston created a vacuum, which only facilitated the fall
of the piston. This caused the cylinder to be cooled between each stroke
and led to the wastage of about four-fifths of all the steam used. It
was to save this that the condenser was invented, in obedience to Watt's
law, as stated in his patent, that "the cylinder should be kept always
as hot as the steam that entered it"; but it must be kept clearly in
mind that Watt's "modified machines," under his first patent, only used
steam to do work upon the upward stroke, where Newcomen used it only to
force up the piston. The double-acting engine--doing work up and
down--came later, and was protected in the second patent of 1780.

Watt knew better than any that although his model had been successful
and was far beyond the Newcomen engine, it was obvious that it could be
improved in many respects--not the least of his reasons for confidence
in its final and more complete triumph.

To these possible improvements, he devoted himself for years. The
records once again remind us