12 
as known. Then the three final equations, obtained by the above 
method, will be 
1. 333e+-49,04 «—43,96p+-48,51—0 
8. 49,04e+117,4032 14+36,4577p—52,3657 —0 
3. —43,96e+36,4579 x+140,2564p—1 62,3572 =0 
These equations give 
p= + 1’, 1277 or 2p=2", 25 
x= 4 0, 1007 or constant of aberration = 20”, 35 
e= —0,0116 or mean N. P. D. Jan. 1, 1819=51°. 29 49”, 92 
Here the differences resulting from supposing z known and un- 
known are not worth notice. 
Observations of y Draconis. 
For this star the mean zenith distance Jan. 1, 1819, has been 
supposed = 1°. 52’ 21”, 13—e. 
Pp, x, and z represent as before. The number of observations are 199. 
The four resulting equations, deduced in the manner that has 
been explained at considerable length, and by a reference to the 
observations for « Lyre, are 
1. 199e+48,76x-—28,90p+22,442:—16,27=0 
2. 48,76e+82,5802« + 35,8977p—20,9436z + 39,9305=0 
3. —28,90e+435,8977 x 4101,6398p—24,93532-+ 26,4376—0 
4. 22,44e—20,9436x—24,9353p+92,5526:—5 | ,8999=0 
These equations give 
z= +0",4246 
p= +0,0704 
v= —0,5056 
= 40,1681] 
This value of 2 z may be considered as not differing more than = of 
