[ I2 S J 
0 
t 
// 
27 
59 
29,6 
+ 
x 3’4 
‘ 2 7 
59 
43 
5 1 
28 
33 
23 
28 
55 
// 
74 5 6 57’ 8 
+ 35> 8 
74 57 33 ‘ 6 
— 5 1 28 3 8 
23 28 55,6 
Or, if the obliquity be required independent of a 
knowledge of the latitude of the place, it will be 
found to be == 23 s 28'' 5 5 // ,3 - 
December 
June 
/•/ 
74 57 33’ 6 
2 7 59 43 
Difference ...... 46 57 50,6 
Mean obliquity 1690, f Diff. 23 28 55,3 
By commparing the obfervations at the fummer 
folftices of 1771 and 1772 with thofe at the winter 
folftice of 1771, it appears that the mean obli- 
quity was about the beginning of the year 1772 
— 23 0 28' 9", 4 and 23 0 28' 8". I fuppofe there- 
fore the mean obliquity to be 23 0 28' 8 /7 at the 
beginning of the prefent year ; and confequently, 
the obliquity has diminifhed, by my obfervations, 
47 // in 81 years, fince Mr. Flamfteed’s time, or at 
the rate of 58''' in 100 years, a quantity which will 
be found nearly at a mean of the computations 
framed by Mr. Euler and Mr. de la Lande, upon, 
the principles of attra&ion. 
Oxford, Dec. 23, 1772. 
•XV. New 
