he various
planets throughout the year.

In order to attain the astronomical knowledge which they seem to have
possessed, the Babylonians must undoubtedly have employed a certain
number of instruments. The invention of sun-dials, as already observed,
is distinctly assigned to them. Besides these contrivances for measuring
time during the day, it is almost certain that they must have possessed
means of measuring time during the night. The clepsydra, or water-clock,
which was in common use among the Greeks as early as the fifth century
before our era, was probably introduced into Greece from the East,
and is likely to have been a Babylonian invention. The astrolabe, an
instrument for measuring the altitude of stars above the horizon, which
was known to Ptolemy, may also reasonably be assigned to them. It has
generally been assumed that they were wholly ignorant of the telescope.
But if the satellites of Saturn are really mentioned, as it is thought
that they are, upon some of the tablets, it will follow--strange as it
may seem to us--that the Babylonians possessed optical instruments of
the nature of telescopes, since it is impossible, even in the clear and
vapor-loss sky of Chaldaea, to discern the faint moons of that distant
planet without lenses. A lens, it must be remembered, with a fair
magnifying power, has been discovered among the Mesopotamian ruins.
A people ingenious enough to discover the magnifying-glass would be
naturally led on to the invention of its opposite. When once lenses
of the two contrary kinds existed, the elements of a telescope were in
being. We could not assume from these data that the discovery was made;
but if it shall ultimately be substantiated that bodies invisible to the
naked eye were observed by the Babylonians, we need feel no difficulty
in ascribing to them the possession of some telescopic instrument.

The astronomical zeal of the Babylonians was in general, it must be
confessed, no simple and pure love of an abstract science. A school of
pure astronomers existed among them; but the bulk of those who engaged
in the study undoubtedly pursued it in the belief that the heavenly
bodies had a mysterious influence, not only upon the seasons, but upon
the lives and actions of men--an influence which it was possible to
discover and to foretell by prolonged and careful observation. The
ancient writers, Biblical and other, state this fact in the strongest
way; and the extant astronomical remai