401 
iron arising from its rotation. 
F T 
(6), and deducing the value of ^ in terms of 6' and and 
depending principally on or the deviation due to rota- 
tion, on the accuracy of the values of which in Table B, I 
place much greater reliance than on those of the absolute 
F r 
values of 6' and 6^. In this manner we obtain 
1 I 3 cos. 2^+1 
sin. (O'— 6 ) \ 3 sin. 2 >, 
sin. (6'+ — 2 COS. I sin. 6' sin. 
\ 
in which the observed values of 6' and corresponding to 
any value of x, being substituted, ought in all cases to give 
the same, or very nearly the same numerical value for 
F T 
? 77 * 
F T 
Table of the values of computed from the several observed values 
ofh' and 6^, in Tables A and B, corresponding to different latitudes. 
X 
Observed values in Table A. 
Computed 
value of 
F r 
Observed values in Table B. 
Computed 
value of 
F r 
6' 
6' 
2/p 
2/P 
0 / // 
0 / // 
0 / n 
0 / // 
0 
+ 47 55 
- 47 55 
17.692 
4 50 28 
N 
0 
1 
18.325 
10 
3 57 20 
2 26 40 
15.658 
4 30 50 
2 54 52 
17.144 
20 
6 57 00 
5 40 00 
16.320 
7 38 05 
6 15 27 
16.678 
30 
9 03 25 
8 03 45 
15.461 
10 07 50 
9 03 *2 
15.824 
40 
9 56 20 
9 19 30 
14.088 
11 02 12 
10 23 37 
14.680 
50 
9 31 20 
9 21 25 
1 1.886 
10 44 55 
10 32 35 
9*983 
60 
8 05 15 
8 16 15 
21.214 
9 12 10 
9 24 40 
21.755 
70 
5 51 35 
6 19 40 
18.328 
6 33 52 
7 06 20 
17.858 
80 
2 51 25 
3 31 30 
17.080 
3 *0 50 
3 56 00 
16.907 
90 
— 22 25 
4 22 25 
16.808 
— 24 49 
4 24 49 
16.397 
Mean value 
16.454 
Mean value 
16.555 
F r 
The values of —r which differ most from the mean, are, in 
f 
both cases, those corresponding to the values of x, 50° and 
60° ; that is nearest to and on contrary sides of the point where 
ft' — = o, which again shows clearly, that the theoretical 
determination of this point does not agree with the observa- 
