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The Engines of Archimedes from the life of Marcellus
Marcellus now moved with his whole army to Syracuse, and, camping
near the wall, proceeded to attack the city both by land and by
sea. The land forces were conducted by Appius: Marcellus, with
sixty galleys, each with five rows of oars, furnished with all
sorts of arms and missiles, and a huge bridge of planks laid upon
eight ships chained together, upon which was carried the engine to
cast stones and darts, assaulted the walls, relying on the
abundance and magnificence of his preparations, and on his own
previous glory; all which, however, were, it would seem, but
trifles for Archimedes and his machines.
These machines he had designed and contrived, not as matters of
any importance, but as mere amusements in geometry; in compliance
with King Hiero's desire and request, some little time before,
that he should reduce to practice some part of his admirable
speculations in science, and by accommodating the theoretical
truth to sensation and ordinary use, bring it more within the
appreciation of people in general. Eudoxus and Archytas had been
the originators of this far-famed and highly prized art of
mechanics, which they employed as an elegant illustration of
geometrical truths, and as a means of sustaining experimentally,
to the satisfaction of the senses, conclusions too intricate for
proof by words and diagrams. As, for example, to solve the
problem, so often required in constructing geometrical figures,
given the two extreme, to find the two mean lines of a proportion,
both these mathematicians had recourse to the aid of instruments,
adapting to their purpose certain curves and sections of lines.
(The 'mesolabes or mesalabium, was the name by which this
instrument was commonly known.) But what with Plato's indignation
at it, and his invectives against it as the mere corruption and
annihilation of the one good of geometry,--which was thus
shamefully turning its back upon the unembodied objects of pure
intelligence to recur to sensation, and to ask help (not to be
obtained without haste subservience and depravation) from matter;
so it was that mechanics came to be separated from geometry, and,
being repudiated and neglected by philosophers, took its place as
a military art. Archimedes, however, in writing to King Hiero,
whose friend and near relation he was, had stated, that given the
force, any weight might be moved, and even boasted, we are told,
relying on the strength of demonstration, that if there were
another earth, by going into it he could remove this. Hiero being
struck with amazement at this, and entreating him to make good
this problem by actual experiment, and show some great weight
moved by a small engine, he fixed accordingly upon a ship of
burden out of the king's arsenal, which could not be drawn out of
the dock without great labor and many men; and, loading her with
many passengers and a full freight, sitting himself the while far
off, with no great endeavor, but only holding the head of the
pulley in his hand and drawing the cord by degrees, he drew the
ship in a straight line, as smoothly and evenly as if she had been
in the sea. The king, astonished at this, and convinced of the
power of the art, prevailed upon Archimedes to make him engines
accommodated to all the purposes, offensive and defensive, of a
siege. These the king himself never made use of, because he spent
almost all his life in a profound quiet, and the highest
influence. But the apparatus was, in a most opportune time, ready
at hand for the Syracusans, and with it also the engineer himself.
When, therefore, the Romans assaulted the walls in two places at
once, fear and consternation stupefied the Syracusans, believing
that nothing was able to resist that violence and those forces.
But when Archimedes began to ply his engines, he at once shot
against the land forces all sorts of missile weapons, and immense
masses of stone that came down with incredible noise and violence,
against which no man could stand; for they knocked down those upon
whom they fell, in heaps, breaking all their ranks and files. In
the mean time huge poles thrust out from the walls over the ships,
sunk some by the great weights which they let down from on high
upon them; others they lifted up into the air by an iron hand or
beak like a crane's beak, and, when they had drawn them up by the
prow, and set them on end upon the poop, they plunged them to the
bottom of the sea; or else the ships, drawn by engines within, and
whirled about, were dashed against steep rocks that stood jutting
out under the walls, with great destruction of the soldiers that
were aboard them. A ship was frequently lifted up to a great
height in the air (a dreadful thing to behold), and was rolled to
and fro, and kept swinging, until the mariners were all thrown
out, when at length it was dashed against the rocks, or let fall.
In the meantime, Marcellus himself brought up his engine upon the
bridge of ships, which was called "Sambuca," from some resemblance
it had to an instrument of music, but while it was as yet
approaching the wall, there was discharged at it a piece of rock
of ten talents' weight, then a second and a third, which, striking
upon it with immense force and with a noise like thunder, broke
all its foundations to pieces, shook out all its fastenings, and
completely dislodged it from the bridge. So Marcellus, doubtful
what counsel to pursue, drew off his ships to a safer distance,
and sounded a retreat to his forces on land. They then took a
resolution of coming up under the walls, if it were possible, in
the night; thinking that as Archimedes used ropes stretched at
length in playing his engines, the soldiers would now be under the
shot, and the darts would, for want of sufficient distance to
throw them, fly over their heads without effect. But he, it
appeared, had long before framed for such occasion engines
accommodated to any distance, and shorter weapons; and had made
numerous small openings in the walls, through which, with engines
of a shorter range, unexpected blows were inflicted on the
assailants. Thus, when they who thought to deceive the defenders
came close up to the walls, instantly a shower of darts and other
missile weapons was again cast upon them. And when stones came
tumbling down perpendicularly upon their heads, and, as it were,
the whole wall shot out arrows at them, they retired. And now,
again, as they were going off, arrows and darts of a longer range
inflicted a great slaughter among them, and their ships were
driven one against another; while they themselves were not able to
retaliate in any way; for Archimedes had fixed most of his engines
immediately under the wall. The Romans, seeing that infinite
mischiefs overwhelmed them from no visible means, began to think
they were fighting with the gods.
Yet Marcellus escaped unhurt, and, deriding his own artificers and
engineers, exclaimed "What! Must we give up fighting with this
geometrical Briareus, who plays pitch and toss with our ships,
and, with the multitude of darts which he showers at a single
moment upon us, really outdoes the hundred-handed giants of
mythology?" The rest of the Syracusans were but the body of
Archimedes' designs, one soul moving and governing all; for,
laying aside all other arms, with his alone they infested the
Romans, and protected themselves. In fine, when such terror had
seized upon the Romans, that, if they did but see a little rope or
a piece of wood from the wall, they instantly cried out, "There it
is again! Archimedes is about to let fly another engine at us,"
and turned their backs and fled, Marcellus desisted from conflicts
and assaults, putting all his hope in a long siege. Yet Archimedes
possessed so high a spirit, so profound a soul, and such treasures
of scientific knowledge, that though these inventions had now
obtained him the renown of more than human sagacity, he yet would
not deign to leave behind him any commentary or writing on such
subjects; but, repudiating as sordid and ignoble the whole trade
of engineering, and every sort of art that lends itself to mere
use and profit, he placed his whole affection and ambition in
those purer speculations where there can be no reference to the
vulgar needs of life; studies, the superiority of which to all
others is unquestioned, and in which the only doubt can be,
whether the beauty and grandeur of the subjects examined, or the
precision and cogency of the methods and means of proof, most
deserve our admiration. It is not possible to find in all geometry
more difficult and intricate questions, or more simple and lucid
explanations. Some ascribe this to his natural genius; while
others think that incredible effort and toil produced these
apparently easy and unlabored results. No amount of investigation
of yours would succeed in attaining the proof, and yet, once seen,
you immediately believe you would have discovered it; by so smooth
and so rapid a path he leads you to the conclusion required. And
thus it ceases to be incredible that (as is commonly told of him),
the charm of his familiar and domestic Siren made him forget his
food and neglect his person, to such a degree that when he was
occasionally carried by absolute violence to bathe, or have his
body anointed, he used to trace geometrical figures in the ashes
of the fire, and diagrams in the oil on his body, being in a state
of entire preoccupation, and, in the truest sense, divinely
possessed with his love and delight in science. His discoveries
were numerous and admirable; and he is said to have requested his
friends and relations that when he was dead, they would place over
his tomb a cylinder containing a sphere, inscribing it with the
ratio of three to two which the containing solid bears to the
contained.
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