MrRIMlV; RHI'ORT ON THE SOUTH GEORGIA EXPKUITIoX. 57 
Tilt' daily observations were made at 8 a. m., and at 2 
and 8 p. m. The figures have not been corrected to a 24-hours' 
mean. The Argentine Observatory, as may be seen from the 
photograph on p. 54, is unfavorably situated for obtaining 
just records of direction and velocity of wind. It is, indeed, 
quite sheltered from the influence of the prevailing south- 
westerh' winils. 
The atmospheric pressure at South Georgia is low, 
though not so low as that observed farther south, the annual 
mean of barometric height being about 745 mm. Great 
changes sometimes occur within short intervals; on April 19, 
1883, a range in the readings of 42.1 mm. was observed during 
the course of twent}-four hours. In the northern hemisphere 
Iceland alone might show the like. The season of lightest 
pressure occurs during September and October (spring), with 
a falling off in November to an average of about 743 mm., 
approaching or equalling the monthly minimum for the year. 
According to the observations of the German Expedition 
(1882-1S83) the lowest readings are never attended by violent 
storms. 
The mean temperature for the year ending September, 
1883. was + 1.7 C: the average for the years 1908, 1909, and 
1912 is + 1.36- C. February (late summer) is the warmest 
month, with an average temperature for five years of + 5.7*^ 
C, June marks the opposite extreme, with an average for 
five years of — 2.01 C, although an average of six years for 
July gives approximately the same figure, — 2.00'' C. The 
remarkably high temperattire given in the table for June. 10 lo, 
namely +6.72' C, does not whollv inspire confidence, and I 
have disregarded it; however, the exceptionally low atmos- 
pheric pressure recorded during that month, as well as the 
excess of cloudiness over the average, indicate that the tem- 
perature may be stated quite correctly. The temperatttre of 
the surface sea water showed an annual mean of + 1.63° C. 
in 1882-1883. The limitations imposed u])on the region by a 
purely oceanic climate are ilhistrated bv the recorded absokite 
maxima and minima of air temperature. +20.7' C. (Febru- 
arv), — 12. ; . ( julv ). 
