Abstract
FURTHER OBSERVATIONS OF HALLEY'S COMET.—In Bulletin No. 20 of the Kadaikanal Observatory Messrs. Michie Smith and John Evershed give an account of the observations of Halley's comet made with various instruments during April and May. A number of photographs, which may fill in the blanks between those taken in America and in Europe, were secured with a 5-inch Grubb portrait lens of 33-8 inches focal length. On certain of these there are many distinct tails and a number of fine details; other plates were exposed in a half-plate Ross camera giving a scale of i mm. = 17.5′. Mr. Evershed used a 91/4-inch reflector, of 74 inches focal length, fed by a 16-inch cœlostat, and secured a number of photographs showing the intricacies of the structure in the head, the scale being 1 mm. = 110″.
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