“August 2, 10h. 9′. The comet is now, with respect to the stars A and B, situated as in fig. 4. Therefore the motion since last night is evident.
“10h. 30′. Another considerable star, C, may be taken into the field with it, by placing A in the centre; when the comet and the other star will both appear in the circumference, as in fig. 5.
“These observations were made with a Newtonian sweeper of 27 inches focal length, and power of about 20. The field of view is 2° 12′. I cannot find the stars A and C in any catalogue, but I suppose they may easily be traced in the heavens; whence the situation of the comet, as it was last night at 10h. 33′, may be pretty nearly ascertained.
“You will do me the favour of communicating these observations to my brother’s astronomical friends.
“I have the honour to be, etc., “CAROLINE HERSCHEL.
“SLOUGH, NEAR WINDSOR, _August 2, 1786_.”
Many also of the nebulæ contained in Sir W. Herschel’s catalogues were detected by her. Indeed the unconquerable industry of the sister challenges our admiration quite as much as the intellectual power of the brother.
We shall not attempt fully to discuss Miss Herschel’s astronomical works. Indeed her labours are so intimately connected with, and are generally so dependent upon, those of her illustrious brother, that an investigation of the latter is absolutely necessary before we can form the most remote idea of the extent of the former. In 1798 she completed “A catalogue of 561 Stars from Flamsteed’s Observations,” contained in the “Historia Cælestis,” but which had escaped the notice of those who framed the “British Catalogue.” For this valuable work which was published, together with a general index of reference to every observation of every star inserted in the “British Catalogue,” at the expense of the Royal Society, in one volume, her brother wrote an introduction. To the utility of these volumes in subsequent researches, Mr. Baily, in the life of Flamsteed, bears ample testimony.
She moreover finished, in 1828, the reduction and arrangement of 2500 nebulæ to the 1st of January, 1800, presenting in one view the results of all Sir William Herschel’s observations on those bodies; and thus bringing to a close half a century spent in astronomical labour, probably unparalleled either in magnitude or importance. But to deliver an eulogy upon her memory is not our purpose. Suffice it to say that her name will live even when the time comes that the astronomical celebrity of a woman will not by the mere circumstance of sex excite the slightest remark.