Page 632 - 89 history of astronomy_opt

and the catalogues to the eleventh.
[Illustration: GREAT COMET, Nov. 14TH,
1882. (Exposure 2hrs. 20m.) By kind per-
mission of Sir David Gill. From this photo-
graph originated all stellar chart-photography.]
This monumental work is nearing com-
pletion. The labour involved was immense,
and the highest skill was required for de-
vising instruments and methods to read off
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