e was always Jamie
to his friends), for such self-abnegation, but the truth of history must
be vindicated for all that. It proclaims, Thou art the man; go up higher
and take your seat there among the immortals, the inventor of the
greatest of all inventions, a great discoverer and one of the noblest of
men!

In this one change lay all the difference between the Newcomen engine,
limited to atmospheric pressure, and the steam engine, capable of
development into the modern engine through the increasing use of the
tremendous force of steam under higher pressures, and improved
conditions from time to time.

Watt leads the steam out of the cylinder and condenses it in a separate
vessel, leaving the cylinder hot. He closes the cylinder top and sends a
circular piston (hitherto all had been square) through it, and closely
stuffs it around to prevent escape of steam. The rapidity of the
"strokes" gained keeps the temperature of the cylinder high; besides, he
encases it and leaves a space between cylinder and covering filled with
steam. Thus he fulfils his law: "The cylinder is kept as hot as the
steam that enters." "How simple!" you exclaim. "Is that all? How
obviously this is the way to do it!" Very true, surprised reader, but
true, also, that no condenser and closed cylinder, no modern steam
engine.

On Monday morning following the Sabbath flash, we find Watt was up
betimes at work upon the new idea. How many hours' sleep he had enjoyed
is not recorded, but it may be imagined that he had several visions of
the condenser during the night. One was to be made at once; he borrowed
from a college friend a brass syringe, the body of which served as a
cylinder. The first condenser vessel was an improvised syringe and a tin
can. From such an acorn the mighty oak was to grow. The experiment was
successful and the invention complete, but Watt saw clearly that years
of unceasing labor might yet pass before the details could all be worked
out and the steam engine appear ready to revolutionise the labor of the
world. During these years, Professor Black was his chief adviser and
encouraged him in hours of disappointment. The true and able friend not
only did this, but furnished him with money needed to enable him to
concentrate all his time and strength upon the task.

Most opportunely, at this juncture, came Watt's marriage, to his cousin
Miss Miller, a lady to whom he had long been deeply attached. Watt's
friends are agreed in statin