the turning of a skillet.

Mathesius, the German author, in 1571; Besson, a philosopher and
mathematician at Orleans; Ramelli, in 1588; Battista Delia Porta, a
Neapolitan mathematician and philosopher, in 1601; Decause, the French
engineer and architect, in 1615; and Branca, an Italian architect, in
1629, all published treatises bearing on the subject of the generation
of steam.

To the next contributor, Edward Somerset, second Marquis of Worcester,
is apparently due the credit of proposing, if not of making, the first
useful steam engine. In the "Century of Scantlings and Inventions",
published in London in 1663, he describes devices showing that he had in
mind the raising of water not only by forcing it from two receivers by
direct steam pressure but also for some sort of reciprocating piston
actuating one end of a lever, the other operating a pump. His
descriptions are rather obscure and no drawings are extant so that it is
difficult to say whether there were any distinctly novel features to his
devices aside from the double action. While there is no direct authentic
record that any of the devices he described were actually constructed,
it is claimed by many that he really built and operated a steam engine
containing pistons.

In 1675, Sir Samuel Moreland was decorated by King Charles II, for a
demonstration of "a certain powerful machine to raise water." Though
there appears to be no record of the design of this machine, the
mathematical dictionary, published in 1822, credits Moreland with the
first account of a steam engine, on which subject he wrote a treatise
that is still preserved in the British Museum.

[Illustration: 397 Horse-power Babcock & Wilcox Boiler in Course of
Erection at the Plant of the Crocker Wheeler Co., Ampere, N. J.]

Dr. Denys Papin, an ingenious Frenchman, invented in 1680 "a steam
digester for extracting marrowy, nourishing juices from bones by
enclosing them in a boiler under heavy pressure," and finding danger
from explosion, added a contrivance which is the first safety valve on
record.

The steam engine first became commercially successful with Thomas
Savery. In 1699, Savery exhibited before the Royal Society of England
(Sir Isaac Newton was President at the time), a model engine which
consisted of two copper receivers alternately connected by a three-way
hand-operated valve, with a boiler and a source of water supply. When
the water in one receiver had been driven out by the st