144 ABSTRACTS FOR THE HORIZONTAL FORCE. 
TABLE XIII.—continued. 
Bifilar Magnetometer. 
Lowest. Highest. 
Gottingen 5 Gottingen P 
Mean Time Reading. Mean Time. Reading. 
1842. ! 5 . Se. Div. Ci Be b Se. Div. 
January 498-8 19 12 
February 501-1 
March 463-7 
April 455-0 
May 508-5 
June 497-7 
July 507-9 
August 507-0 
September 503-6 
October 514-7 
November 522-4 
December 529-1 
i 
AN TAwWwOAnoe 
The range, in parts of the whole horizontal force of the five terms of 1841, is about 0:01060. The greatest 
and least occurring in the October term, being 0-0571 below, and 0-00489 above the mean of the month in Table X. 
The range of the terms of 1842 is 0.01242. The least being 0.00696 below the mean of the month in 
April ; and the greatest 0-00546 above the mean of the month in September. 
TABLE XIV.—The lowest and highest Readings of the Bifilar Magnetometer during Extra Observations for 
each Month, in which Extra Observations were made. 
Bifilar Magnetometer. 
Lowest. Highest. 
Gottingen : Gottingen r 
Mean Time. Meany Mean Time. Reading. 
1841. a. jh. mi) ‘8. Se. Div. a hm s Sc. Div. 
August 20 22 42 30 517-9 20 23 2 30 520-7 
September 25 629-8 25 4 23 55 903-7 
1842. 
May 
July 
August 
September 
October 
November 
December 
528-8 
273-1 
479-8 
498-7 
519-9 
492-2 
496-2 
555-4 
621-1 
574-0 
567-3 
545-3 
537-2 
545-8 
oocoocoeco 
cooocoo 
The range of the observed portion of the disturbance, September 1841, is 0-04168 ; the lowest being 0.01207 
above, and the highest 0-05370 above the mean of the month. 
The range of the observed disturbances of 1842 occurs in July, and is 004350. The lowest being 0.03059 
below, and the highest 0-01291 above the mean of the month. 
The range of all the observations in 1841 is about 0-06130. The lowest being in the Daily Observation, — 
November 18.=0-00760 below the mean of the month ; the highest 0:05370 above the mean of the month, occurs 
in the disturbance September 1841. 
The range of all the observations in 1842 occurs in the July disturbance given above. 
