Steam Steel and Electricity | Page 4

measure, as the supposed rod against the tree would. It gives way, and
is elastic, but not as quickly as the force of the explosion acts, and the
gun is pushed backwards. It is the turbine principle, running into
hundreds of uses in mechanics.] He made a closed vessel from whose
opposite sides radiated two hollow arms with holes in their sides, the
holes being on opposite sides of the tubes from each other. This vessel
he mounted on an upright spindle, and put water in it and heated the
water. The steam issuing from the holes in the arms drove them
backward. The principle of the action of Hero's machine has been
accepted for two thousand years, though never in a steam-engine. It
exists under all circumstances similar to his. In water, in the turbine
wheel, it has been made most efficacious. The power applied now for
the harnessing of Niagara for the purpose of sending electric currents
hundreds of miles is the turbine wheel.
[Illustration: THE SUPPOSED HERO ENGINE.]
Hero appears to the popular imagination as the greatest inventor of the
past. Every school boy knows him. Archimedes, the Greek, was the
greater, and a hundred and fifty years the earlier, and was the author of
the significance of the word "Eureka," as we use it now. But Hero was
the pioneer in steam. He made the first steam-engine, and is immortal
through a toy.
The first practical device in which expansion was used seems to have
been for the exploiting of an ecclesiastical trick intended to impress the
populace. There is a saying by an antique wit that no two priests or
augurs could ever meet and look at each other without a knowing wink
of recognition. Hero is said to have been the author of this contrivance
also. The temple doors would open by themselves when the fire burned
on the altar, and would close again when that fire was extinguished,
and the worshippers would think it a miracle. It is interesting because it
contained the principle upon which was afterwards attempted to be
made the first working low-pressure or atmospheric steam-engine. Yet
it was not steam, but air, that was used. A hollow altar containing air

was heated by the fire being kindled upon it. The air expanded and
passed through a pipe into a vessel below containing water. It pressed
the water out through another pipe into a bucket which, being thereby
made heavier, pulled open the temple doors. When the fire went out
again there was a partial vacuum in the vessel that had held the water at
first, and the water was sucked back through the pipe out of the bucket.
That became lighter again and allowed the doors to close with a
counter-weight. All that was then necessary to convince the populace of
the genuineness of the seeming miracle was to keep them from
understanding it. The machinery was under the floor. There have been
thousands of miracles since then performed by natural agencies, and
there have passed many ages since Hero's machine during which not to
understand a thing was to believe it to be supernatural.
[Illustration: THE TEMPLE-DOOR TRICK.]
From the time of Hero until the seventeenth century there is no record
of any attempt being made to utilize steam-pressure for a practical
purpose. The fact seems strange only because steam-power is so
prominent a fact with ourselves. The ages that intervened were, as a
whole, times of the densest superstition. The human mind was active,
but it was entirely occupied with miracle and semi-miracle; in astrology,
magic and alchemy; in trying to find the key to the supernatural. Every
thinker, every educated man, every man who knew more than the rest,
was bent upon finding this key for himself, so that he might use it for
his own advantage. During all those ages there was no idea of the
natural sciences. The key they lacked, and never found, that would
have opened all, is the fact that in the realm of science and experiment
there is no supernatural, and only eternal law; that cause produces its
effect invariably. Even Kepler, the discoverer of the three great laws
that stand as the foundation of the Copernican system of the universe,
was in his investigations under the influence of astrological and
cabalistic superstitions. [Footnote: Kepler, a German, lived between
1571 and 1630. His life was full of vicissitudes, in the midst of which
he performed an astonishing Even the science of amount of intellectual
labor, with lasting results. He was the personal friend of Galileo and
Tycho Brahe, and his life may be said to have been spent in finding the

abstract intelligible reason for the actual disposition of the solar system,
in which physical cause should take the place of arbitrary