DEAR SIR,—I like the 18-inch speculum, and I think it as good as it can be, and if the larger one is as good I shall be delighted with it. It gives beautiful star images: I see Sirius as a brilliant dot, a glorious object without ray or flares of any kind. I never saw it so well before.
37, EATON RISE, EALING, _February 3rd, 1877_.
DEAR SIR,—I have tried the 18-inch speculum on some tests, and especially the satellites of Uranus, and it appears fine, very fine. What I have done in photography promises well.
MY DEAR SIR,—Circumstances have prevented me from making many observations of late, but I am more confirmed in my opinion that my telescope of your make is a very fine instrument. (A 6-1/2-inch.) I heartily wish you success, which I feel sure you will obtain, as you are so painstaking and turn out a thoroughly reliable article. I shall be curious to compare my brother’s telescope with mine.
DEAR SIR,—You have asked me for my opinion of the 10-inch speculum. I have tested it, and can speak in the highest terms of its performance. Definition in good air is as near perfection as it is possible to imagine. Such tests as ζ Cancri, γ^2 Andromedæ are well divided. The 6th star in the trapezium stands out well clear of its brighter neighbour. On the moon any power may be applied, only lessening the light, but retaining sharpness of outline. I have tried a good many telescopes, but never yet saw these 10-inch mirrors surpassed. The image of a star disc expanded on each side of the focus is of as nearly the same appearance as possible.
DEAR SIR,—In compliance with your request, I send particulars of my observation on φ Draconis. It was about 12.45 this morning when I directed my 8-1/2-inch to this object, the air was very unsteady, in fact not nearly so good as some nights lately, and I well divided it with a power of 450. I then used a 6-1/2-inch stop, which I found very much increased the steadiness of definition.
DEAR SIR,—I tried the 6-1/4-inch mirror I had from you for the first time last night. The night was not a good one for definition, but I was very much pleased indeed with its performance.
DEAR SIR,—I have been wishing to tell you how pleased I am at the performance of your mirror. Many thanks for your kind offer to change the mirror if needful, but I think it could hardly be better than it is, its performance on different double stars is most excellent. I have examined nearly 100 of these since September with the 6-1/2-inch, most of them very difficult, but the mirror came out well under all tests. I send you a list of some of the objects I have examined.