Page 344 - 89 history of astronomy_opt

It is interesting to trace historically the
invention of those instruments of precision
which have led to this result, and, without
entering on the details required in a practi-
cal handbook, to note the guiding principles
of construction in different ages.
It is very probable that the Chaldeans
may have made spheres, like the armillary
sphere, for representing the poles of the heav-
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