478 MR JOHN ALLAN BROUN ON THE BIFILAR MAGNETOMETER, 
TABLE V1.—Sums or DirFERENCES OF BIFILAR DAILY MEANS. 



eS 





—— 



1844, Nov. 34:46 | 13:79 | 0:40 |1845. Sept. 19°41 512 | 0-26 
Dee. 38:03 | 21-01 | 0-55 Oct. 32:39 | 7:55 | 0-23 
1845. 
The final value is 
,_ 256-75 
== = 0°438 se. div., with a probable error of 0°04 sc. div.; © 
1 ~ 586-24 P 
whence, since 
k = 0:00022 
[9g] = 0-000096 
By water experiments, 
q = 0:000220 
Therefore, 
[q] = 0°484 gq. 
26. St HELENA, 1842-43.—The series of published observations in my pos- 
session extends till December 1843.* As the daily differences of temperature 
are small, the sums for each two months of the same name in 1842-43 are given; 
and as the majority of the daily differences of temperature were under half a 
degree Fahr., the sums were also taken for those days only for which the mean 
temperature of the following day differed half a degree or more. The results by 
both methods are given in the following Table :— 
* Printed under the superintendence of Lieut.-Colonel E. SaBrne, 

