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result with half-an-hour’s exposure was good,
so he tried three hours. The result was
such a display of sharp star images that he
resolved on the Cape Photographic Durch-
musterung, which after fourteen years, with
Kapteyn’s aid in reducing, was completed.
Meanwhile the brothers Henry, of Paris, were
engaged in going over Chacornac’s zodia-
cal stars, and were about to catalogue the
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