390 HISTORY OF ASTRONOMY. 



stars. I have already seen Enceladus pretty steadily at 

 the conj unctions ; and on the 18th he was so plainl y 

 visible near his eastern elongation that I detected 

 him before I had quite brought the eye-piece up to 

 focus." 



2. A telescope of 7f inches aperture, still on hand. 



3. A telescope of 7|- inches aperture and 9| feet focal 

 length, was sold to Eev. W. E. Dawes and sent to En- 

 gland in March, 1854. The following are the remarks of 

 Mr. Dawes respecting it : 



" Though the crown-glass has a considerable number 

 of small bubbles, the performance of the telescope is not 

 sensibly affected by that circumstance. In other respects 

 the materials are good ; and the figure is so excellent, and 

 so uniform throughout the whole of the area, that its 

 power is quite equal to any thing which can be expected 

 of the aperture ; and consequently both in its illuminat- 

 ing and refracting powers, it is decidedly superior to my 

 old favorite of 6 inches aperture. As a specimen of its 

 light, I may mention the companion of v Ursa Majoris as 

 having been pretty steadily seen with it ; and also that I 

 have never seen Saturn under tolerable circumstances 

 during the present apparition without detecting Encela- 

 dus, even when at or very near his conjunction with the 

 planet. When exterior to or tangent to the extremity of 

 the ring, this satellite has frequently been perceived as 

 soon as my eye was applied to the telescope. Last 

 spring, it was seen several times in strong twilight. In 



