FROM J. F. W. HERSCHEL TO MISS HERSCHEL.
LONDON, April 18 1825.
I received this afternoon your most valuable packet containing your labours of the last year, which I shall prize, and more than prize—shall use myself, and make useful to others. A week ago I had the twenty-foot directed on the nebulæ in Virgo, and determined afresh the right ascensions and polar distances of thirty-six of them. These curious objects (having now nearly finished the double stars) I shall now take into my especial charge—nobody else can see them. I hope very soon (in a fortnight or three weeks) to be able to transmit to you and to MM. Gauss and Harding our work (Mr. South's and my own) on the double stars, in which you will find some of my father's most interesting discoveries placed beyond the reach of doubt. It will contain measures of the position and distance of 380 double stars. But Mr. South, who is an industrious astronomer (almost as much so as yourself), has just sent me complete and accurate measures of 279 more, making in all 659. Among these we have now verified not less than seventeen connected in binary systems in the way pointed out by my father, and twenty-eight at least in which no doubt of a material change having taken place can exist. M. Struve, at Dorpat, and M. Amici, in Italy, have also taken up the subject of double stars, and are prosecuting it with vigour.
I am particularly obliged to you for my father's letters and pocket-book—they are to me a real treasure. The style of the Éloge in the Moniteur is very inferior to what I expected from Fourier; but on the whole it contains nothing materially untrue. The publications enclosed were very acceptable. I wish my uncle had not confined himself to a