620 LAMONT: MAGNETIC RESULTS 
If we make n = + 0°:0040 and m = 0, we obtain 
9°52264 
9°52254 
9°52272; 
but if we make n = — 000280 and m = + 0:00880, we obtain 
9°52339 
9°52339 
SO b2300~ 
If with Professor Lloyd we regard the agreement of the num- 
bers as they are as sufficient, then in the mean 
log 2 a = 9°52252; 
if we amend these numbers by a second member, the agreement 
becomes better, but the value becomes somewhat greater, namely, 
log 2 = = 9°52258; 
lastly, if we add a third member we may make the accordance 
complete, but the value mounts up to 
log 2 — = 9°52339 ; 
in a word, if the distances are chosen large, the amendments de- 
pending on the higher members may still be considerable* ; but 
it is impossible to determine them with certainty, because the 
coefficients of m form a slowly decreasing series, and the values 
of e tan $ must be considerably increased or diminished to equate 
small differences. It is therefore absolutely necessary to choose 
smaller distances and greater angles of deflection. 
It would still remain to remark that Mr. Lloyd has neglected 
the member 
Ul 
15 a sin? >, 
while in the cases adduced by him it amounted to 745. But no 
method which leaves out such considerable quantities can lay 
claim to exactness. There would however be no difficulty in 
remedying this defect. 
Besides the objections which relate to the determination of 
the constants, we may also mention, as against the facility of 
* Mr. Lloyd’s hypothesis gives 
p=0 g=— 0:000655, 
thence 
p=O0 d= — 0000284; 
