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Page 18
In 120 B.C., Hero of Alexandria made a machine to be driven by steam. It
consisted of a hollow sphere into which the steam was admitted;
projecting from the sphere were two arms, from which the steam escaped
by three holes on the side of _each_ arm opposite to that of the
direction of its revolution, which, by removing the power from off the
one part of _each_ arm, caused it to revolve in the direction opposite
to that of the hole that allowed the steam to escape. This kind of
engine has been for some years in use by Mr. Ruthven of Edinburgh. There
are others who have followed very closely on Hero's plan in more ways
than one; for instance, it is the common Barker's mill, though with this
difference, that his mill is driven by water instead of steam: Avery,
also, made a steam-engine almost exactly the same. I may here, perhaps,
just be allowed to mention what a little water and coal will produce, as
it will show at once from whence our power is derived. "A pint of water
may be evaporated by two ounces of coal; in its evaporation it swells to
216 gallons of steam, with a mechanical force equal to raising a weight
of thirty-seven tons one foot high." A pound of coal in a locomotive
will evaporate about five pints of water, and in their evaporation these
will exert a force equal to drawing two tons on a railway a distance of
one mile in two minutes. A train of eighty tons weight will take 240
passengers and luggage from Liverpool to Birmingham and back, each
journey about four and a quarter hours; this double journey of 190 miles
being effected by the combustion of one and a half tons of coke, worth
about twenty-four shillings. To perform the same work by common road
would require twenty coaches, and an establishment of 3800 horses, with
which the journey would be performed each way in about twelve hours,
stoppages included. So much for the advantages of steam.
The Romans are supposed to have had some knowledge of the power of
steam. Among amusing anecdotes, showing the knowledge the ancients had
of steam, it is told that Anthemius, the architect of Saint Sophia,
lived next door to Zeno. There existed a feud between them, and to annoy
his neighbour, Anthemius had some boilers placed in his house containing
water, with a flexible tube which he could pass through a hole in the
wall under the floor of Zeno's dwelling; he then lit a fire, which soon
caused steam to pass through the tube in such a quantity as to make the
floors to heave as if by an earthquake. But to return. We next come to
Blasco de Garay (A.D. 1543), who proposed to propel a ship by the power
of steam. So much cold water seems to have been thrown on his engine,
that it must have condensed all his steam, as little notice is taken of
it except that he got no encouragement. We find that it has also been
used by some of the ancients in connection with their deities.
Rusterich, one of the Teutonic gods, which was found in an excavation,
proves how the priests deceived the people. The head of this one was
made of metal and contained a pot of water. The mouth and another hole
in the forehead being stopped by wooden plugs, a fire of charcoal was
lighted under this pot of water, and at length the steam drove out the
plugs with a great noise, and the god was shrouded in a mist of steam
which concealed him from his astonished worshippers.
In 1629, Giovanni Branca of Loretto in Italy, an engineer and architect,
proposed to work mills and other machinery by steam blowing against
vanes, much in the same way as water does in turning a wheel. The waste
of steam in such a plan is so obvious, that it is not to be wondered at
that it did not produce any great results, as we all know that the
moment we let steam out of his case, the case is all up with him, and he
dies a natural death. He is a most delicate yet powerful agent, and
requires to be kept warm in all weathers--this fact does not seem to
have struck Mons. Branca when he let him out of his boiler.
The next person we come to, and perhaps the first of any note, is the
Marquis of Worcester in 1663 (died 1667). He was a man who seems, as far
as history tells us, to have taken a great interest in furthering the
advancement of steam. He was not contented with one invention, but
published a book entitled "A Century of Inventions," and in this work he
describes a means of raising water by the pressure of steam. The Marquis
appears to have been a politician as well as an inventor, as we find he
was engaged on the side of the Royalists in the Civil Wars of the
Revolution, lost his fortune and went to Ireland, where he was
imprisoned. Escaping to France, from thence he returned to London as a
secret agent of Charles II., but was detected and imprisoned in the
Tower, where he remained till the Restoration, when he was set at
liberty. One day, while in prison, he observed the lid of the pot in
which his dinner was being prepared lifted up by the vapour of the water
boiling inside. Reflecting on this, he turned his mind to the matter,
and thought that this vapour, if rightly applied, might be made a useful
moving power. He thus describes his invention in his 68th Article: "I
have contrived an admirable way to drive up water by fire, not by
drawing or sucking it upwards, thirty-two feet. But this way hath no
bounds, if the vessels be strong enough." He then goes on to say, that
"having a way to make his vessels, so that they are strengthened by the
force within, I have seen the water run like a constant stream forty
feet high. One vessel rarified by fire driveth forty of cold water, and
one being consumed, another begins to force, and refill with cold water,
and so on successively, the fire being kept constant. The engineman
having only to turn two cocks, so as to connect the steam with the one
or the other vessel."
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