224 ABSTRACTS OF THE MAKERSTOUN OBSERVATIONS, 1843. 
TABLE IIl.—Mean Westerly Declination at the Observation Hours for each Month in 1843. 
Month. 
1843. 
January 
February 
March 
April 
May 
June 
July 
August 
September 
October 
November 
December 
Mean : : : 26-10 
The above Table is intended chiefly as a key for comparing the tabular observations. 
The mean at 18" in January is rendered comparable with the means at the other hours thus: the daily means 
from January 9 to 14, being the means of 8 daily observations, were corrected by — 0':14, obtained, as for Table I., 
in order to reduce them to the mean of 9 daily observations, then 
’ 
Mean Westerly Declination, January 9—31, is 5 ; 2 5 = 25:83 
eee cee cee eee wee eee see cee eee cee January 16—31, 4 | 96:25 
Difference, ? i R : : : Sn 
The mean for 18", deduced from the observations January 16—31, was therefore corrected by —0-’42, in 
order to reduce it to the mean from January 9—31 as for the other hours. 
SECULAR CHANGE. 
By comparing the means at 20", 23", 2", and 5", the observation hours in 1842 (Table I., p. 136, 1842), 
9h 4 Qh h4@h 
with the means at 20%, oe 2 and — for 1843, we obtain the following results for the yearly retro- 
gression of westerly declination :— 
204 23h 2b 5h 
1842, 26°61 29°80 33°80 30°40 
1843, 20:89 24:22 28°23 24.80 
Difference, 5:72 5:58 5:57 5:60 
IGCHTE, SER RAe eRe Ors 
