342 Mr. herschel’s AJlronomical Obfervations 
— o’clock, o ceti being now in the meridian, is almoft 
of a middle fize between aldebaran and a. arietis. Its ap- 
parent diameter by the telefcope is alfo increafed. 
Nov. 2, 1779, The luftre of the periodical ftar is Hill 
increafed. The body is very full and round in the tele- 
fcope. I magnified it 449 times very diftindtly, the 
evening being fo fine ; but my ufual power is only 222. 
Nov. 20, 1779? The periodical ftar feemed to be as 
bright as before, but no brighter. 
Nov. 30, 1779, 0 cet i is confiderably decreafed. Its 
magnitude is lefs than /$ but greater than «. I have be- 
fore remarked, that is lefs than /3. 
Dec. 4, 1779, The luftre of 0 ceti is only equal to «. 
I meafured the diftance of this ftar from the obfcure one 
which follows it : 
% 
Firft meafure, 1' 5 3". 4.37 
Second meafure, 1' 50^.625 
The weather was fo cold, that I could hardly finiftv 
this laft meafure ; but I believe it to be too fmall. The 
difagreement is owing to the difficulty, and not to want 
of accuracy in the micrometer. 
Jan. 4, 1780, The periodical ftar is very much dimi- 
nifhecl. I took the diftance, but the evening was very 
indifferent, and therefore the fmall ftar fo faint as to al- 
low but little light. It meafured T 45 // -937. I thought 
the 
