an
engine which had the essential features of the modern turbine, but his
crude apparatus lacked efficiency.

Once more the coal-mines of England set invention working on a
definite, continuous {8} object. As the shafts were sunk to lower and
lower levels, it became impossible to pump the water out of the mines
by horse power, and the aid of steam was sought. Just at the close of
the seventeenth century Savery devised the first commercial
steam-engine, or rather steam fountain, which applied cold water to the
outside of the cylinder to condense the steam inside and produce a
vacuum; while Papin, one of the Huguenot refugees to whom industrial
England owed so much, planned the first cylinder and piston engine.
Then in 1705 Newcomen and Cawley, working with Savery, took up Papin's
idea, separated boiler from cylinder, and thus produced a vacuum into
which atmospheric pressure forced the piston and worked the pump. Next
Humphrey Potter, a youngster hired to open and shut the valves of a
Newcomen engine, made it self-acting by tying cords to the engine-beam,
had his hour for play or idling, and proved that if necessity is the
mother of invention, laziness is sometimes its father. Half a century
passed without material advance; even as perfected in detail by
Smeaton, the Newcomen engine required thirty-five pounds of coal to
produce one horse-power per hour, as against one pound {9} to-day.
Then James Watt, instrument-maker in Glasgow, seeing that much of the
waste of steam was due to the alternate chilling and heating of the
cylinder, added a separate condenser in which to do the chilling, and
kept the temperature of the cylinder uniform by applying a
steam-jacket. Later, by applying steam and a vacuum to each side of
the piston alternately, and by other improvements, Watt, with his
partner Boulton, brought the reciprocating steam-engine to a high stage
of efficiency.

It took fifty years longer to combine the steam-engine and the rail.
French and American inventors devised steam carriages, which came to
nothing. England again led the way. At Redruth in Cornwall Boulton
and Watt had a branch for the erection of stationary engines in Cornish
tin-mines, in charge of William Murdock, later known as inventor of the
system of lighting by gas. Murdock devised a steam carriage to run
upon the ordinary highway, but was discouraged by his employers from
perfecting the machine. Another mechanic at Redruth, Richard
Trevit