70 
Dr. Brinkley on the 
This is as great a coincidence, allowing for unavoidable 
errors, as could be expected from the most uniform variation. 
The difference that exists between the 2nd and 3rd, is con- 
trary to a southern motion 
(2)7 Draconis and u Cygni, 
Dunkirk, 
Greenwich, 
Palermo, 
Dublin, 
1740, Z. D. 
1755, decl. 
1 800, decl. 
1823, N.P.D. 
y Draconis 
o° 29' 47", 0 N 
5i°3i'4°",6 
5*° 3 1 ' 4" »5 
38° 29' io", 3 
a Cygni - 
6 40 12 ,8 S 
44 2 4 5 6 >7 
44 34 19 > 8 
45 20 52 ,0 
Diff. 
^4 
VO 
v-n 
VO 
00 
7 6 43 ,9 
6 56 44 ,7 
6 51 41 ,7 
7 9 59 > 8 
7 6 43 ,9 
6 56 44 ,7 
05 y-) 3 »S >9 
(45 y-) 9 59 >2 
(23 y.) 5 3 ,0 
The secular variation of annual precession in diff of decl. 
= +, 202 — , 227 = — ,025. 
Hence, 
Rate at 1747 1 f 2' io",6'J f 2' 10", 7 
at 1 777 lin ten years-! 2 13 ,1 }• reduced to i78o< 2 13 ,1 
at 1 8 1 2 J [2 11 ,7j [211,6 
The coincidence here is not so great as before, but there 
is nothing the least in favour of a southern motion in a. Cygni. 
(III.) The observations* made by the late General Mudge, 
with the zenith sector, in 1802, appear to concur in evidence 
against the southern motion, by a comparison of the place 
of Capella with those of y and y Ursas Maj. and y Draconis. 
The instrument with which these observations were made, 
and the care-f used in making them, entitle them to great 
weight. 
* Philosophical Transactions, 1803. 
f It is necessary to remark, that the computations, as given in the Philosophical 
Transactions, were not made with the same care as the observations. This ex- 
plains the different results which appear here. For Capella, the lunar nutation 
appears to have been anplied the wrong way. 
