Page 413 - 89 history of astronomy_opt

an object-glass prism for spectroscopic work.
It would be out of place to describe here
the practical adjuncts of a modern equatoreal–
the adjustments for pointing it, the clock
for driving it, the position-micrometer and
various eye-pieces, the photographic and spec-
troscopic attachments, the revolving domes,
observing seats, and rising floors and differ-
ent forms of mounting, the siderostats and
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