But as perhaps several days might pass before I could have any answer to my letters, or my brother return, I would not wish to be thought neglectful, and therefore if you think, sir, the following description is sufficient, and that more of my brother’s astronomical friends should be made acquainted with it, I should be very happy if you would be so kind as to do it for the sake of astronomy. The comet is a little more than 3½° following α Andromedæ, and about 1½° above the parallel of that star. I saw it first on April 17th, 16^h 24ʹ sidereal time, and the first view I could have of it last night was 16^h 5ʹ. As far as I am able to judge, it has decreased in P. D. nearly 1°, and increased in A. R. something above 1ʹ. These are only estimations from the field of view, and I only mention it to show that its motion is not so very rapid. I am, &c., C. H. [Sidenote: 1790. _Letters about the Third Comet._] MISS HERSCHEL TO ALEX. AUBERT, ESQ. SLOUGH, _April 18, 1790_. DEAR SIR,— I am almost ashamed to write to you, because I never think of doing so but when I am in distress. I found last night, at 16^h 24ʹ sidereal time, a comet, and do not know what to do with it, for my new sweeper is not half finished; and besides, I broke the handle of the perpendicular motion in my brother’s absence (who is on a little tour into Yorkshire). He has furnished me to that instrument a Rumboides, but the wires are too thin, and I have no contrivance for illuminating them. All my hopes were that I should not find anything which would make me feel the want of these things in his absence; but, as it happens, here is an object in a place where there is no nebula, or anything which could look like a comet, and I would be much obliged to you, sir, if you would look at the place where the annexed eye-draft will direct you to. My brother has swept that part of the heavens, and has many nebulæ there, but none which I must expect to see with my instrument. I will not write to Sir J. Banks or Dr. Maskelyne, or anybody, till you, sir, have seen it; but if you could, without much trouble, give my best respects and that part of this letter which points out the place of the comet to Mr. Wollaston, you would make me very happy. I am, dear sir, &c., &c., C. H. SIR JOSEPH BANKS TO MISS HERSCHEL. SOHO SQUARE, _April 20, 1790_. MADAM,— I return you many thanks for the communication you were so good as to make to me this day of your discovery of a comet. I shall take care to make our astronomical friends acquainted with the obligations they are under to your diligence.