1863.] 515 



6-386 x 5 2400 -r 53- 706 6260-5 X 983-8^-900 



= 62307 =6842-5 



26-1 for 6000 13*6 q 



3-7 diff. for 230 181-Q-p 



6260-5 A H=6838-l 

 Result by Laplace's formula 6838-2. 



These results are obtained by transforming Laplace's formula as 

 follows. The original expression in the Mec. Gel. vol. iv. p. 293, 

 reduced to English measures and the present notation, is 



A-H=60158-71 . (1 + 0-002845 cos2L) . 836 + ^ + a } 



/i\ 



fe?-- 868589 ] 1 " 



which Delcros has transformed (in f Annuaire Meteorologique de la 



France' for 1849) to the equivalent of 



h H=6015871 x [log B log 5-0-0000389278 . (M m)] 



The last factor may be split into the two 



without sensible error. Then, since 



60158-71 x A+ ^1^=60309-19 



and 60309-19 x 0-0000389278=2-34770, 



if we put h H for the product of the three first factors on the 



right-hand side in (c), we find 



A-H=[60309-19.(logB-log5)-~2-34770.(M~m)]. 836+A+a 



Putting 2-35 for 2-34770, and I, h 11 , H" for their values, this form 

 (d) will be identical with (a), provided that 



60309-19. 



