On the Origin of Clockwork, Perpetual Motion Devices, and the Compass — John Shaqi
On the Origin of Clockwork, Perpetual Motion Devices, and the CompassPrice, Derek J. de Solla (Derek John de Solla)
History
On the Origin of Clockwork, Perpetual Motion Devices, and the Compass
Price, Derek J. de Solla (Derek John de Solla)
Clocks and watches; Horology
Gaius Sulpicius Gallus ... at a time when ... he happened
to be at the house of Marcus Marcellus, his colleague in
the consulship [166 B.C.], ordered the celestial globe to
be brought out which the grandfather of Marcellus had
carried off from Syracuse, when that very rich and
beautiful city was taken [212 B.C.].... Though I had heard
this globe (sphaerae) mentioned quite frequently on
account of the fame of Archimedes, when I saw it I did not
particularly admire it; for that other celestial globe,
also constructed by Archimedes, which the same Marcellus
placed in the temple of Virtue, is more beautiful as well
as more widely known among the people. But when Gallus
began to give a very learned explanation of the device, I
concluded that the famous Sicilian had been endowed with
greater genius than one would imagine possible for human
being to possess. For Gallus told us that the other kind
of celestial globe, which was solid and contained no
hollow space, was a very early invention, the first one of
that kind having been constructed by Thales of Miletus,
and later marked by Eudoxus of Cnidus--a disciple of
Plato, it was claimed--with constellations and stars which
are fixed in the sky. He also said that many years later
Aratus ... had described it in verse.... But this newer
kind of globe, he said, on which were delineated the
motions of the sun and moon and of those five stars which
are called wanderers, or, as we might say, rovers
[_i. e._, the five planets], contained more than could be
shown on the solid globe, and the invention of Archimedes
deserved special admiration because he had thought out a
way to represent accurately by a single device for turning
the globe, those various and divergent movements with
their different rates of speed. And when Gallus moved
[_i.e._, set in motion] the globe, it was actually true
that the moon was always as many revolutions behind the
sun on the _bronze_ contrivance as would agree with the
number of days it was behind in the sky. Thus the same
eclipse of the sun happened on the globe as would actually
happen, and the moon came to the point where the shadow of
the earth was at the very time when the sun (appeared?)
out of the region ... [several pages are missing in the
manuscript; there is only one].
_De republica_, I, xiv (21-22), Keyes' translation.
When Archimedes put together in a globe the movements of
the moon, sun and five wandering [planets], he brought
about the same effect as that which the god of Plato did
in the Timaeus when he made the world, so that one
revolution produced dissimilar movements of delay and
acceleration.
_Tusculanae disputationes_, I, 63.
Later descriptions from Ovid, Lactantius, Claudian, Sextus Empiricus,
and Pappus, respectively, are (italics supplied):
Public-domain text, read in full here on John Shaqi.
Reviews
Reviews
No reviews yet
Be the first to share your thoughts on this work.
Join the Discussion
Join the discussion
Sign in to leave a comment or review.
Sign InorCreate an account