Mr, pigott’s Account of double Stars, See. 8^ 
declinations were deduced from the difference of altitudes be- 
tween the double ftars and the known ftars, to which they were 
compared, as fhewn by the graduated femi-circle of the tranfit 
inftrument, which, being divided to two minutes only, cannot 
be fuppofed to give any great precifion : however, I believe, 
their declinations, hence deduced, to be correct to one minute, 
nr one minute and a half 
In observing the double ftar compared to f Pegafi, I found it 
impoffible to illuminate the wires of the tranfit inftrument, 
without nearly obliterating the ftar. This difficulty led me to 
a method, which, as it completely fucceeded, may, under fimi- 
lar circumftances, poftibly be of ufe to others. A perfon illu- 
minating the wires very faintly, fo that I could juft perceive the 
double ftar, at a fignal totally withdrew the light : this fignal 
I made when the double ftar was nearly as far diftant from the 
ijrft wire as the five wires are diftant from each other, which, 
in this cafe, was i y by the clock* I then counted the feconds, 
and did not fail to fee the ftar difappear a fecond or two within 
the time expected. On its difappearing, I made a fignal to 
write down ; and then beginning to count again, did the 
fame at each wire. I have fince tried this method with other 
ftars, and think they may be thus obferved, even with greater 
precifion than when the wires are illuminated. Hence the 
troublefome bufinefs, well known to aftronomers, of illumi- 
nating faint* objects, may be removed. 
The preceding ftar of each double ftar was obferved on the 
firft, third and fifth wires, and the following one on the fecond 
and fourth wires ; and thus their difference in R. A. in time, 
converted into parts of a great circle, obtained. Suppofing the 
apparent R. A. and App. declinations of « Delphini, @ Aquarii, 
and f Pegafi, as here affumed, the places of thefe double ftars 
were found to be as follows. 
I beg 
