Temperature of the Year. 37 
ive hours. The record was, however, discontinued every week 
from Saturday, 7, P. M. to Sunday, 7, P.M. During a part of 
the long autumnal vacation, when few students remained in town, 
the record was made but once in two or three hours by night, 
and the intermediate numbers were supplied by interpolation. 
Throughout the year, I almost every day attended personally to 
the location of the thermometer, that it might have such an ex- 
posure as to indicate correctly the temperature of the air. The 
entire number of observations was seven thousand five hundred 
and twelve, distributed equally through the year, or about six 
hundred and twenty-six each month. The following table ex- 
hibits the mean temperature of the several months, and of the 
year, according to Fahrenheit’s thermometer. 
Feb. 
28°57 
Mar. 
34:81 
Oct. 
50. 46 
Noy. 
34: 80 
Dec. 
29% 98)47. is 
June. Year. 
161.60 
Jan. 
92°04 
April. 
48.54 
May. 
56.02 
July. 
71 61 
Aug. 
ve 44 
Sept. 
50. 30 
Besides the daily, monthly, and annual averages, I also obtained 
the averages of the corresponding hours for every month, and 
for the year. Thus, in January, the mean temperature at 1, A: 
M., was 199.04; at 2, A. M., 18°.70, &c. All these retulte:ers 
sensaniall at once to the eye in the plate, in which the mean diur- 
nal changes of each month are represented by a curve, whose 
coordinates show respectively the hour of the day and the degree 
of temperature. The horizontal ordinates indicate the hours ac- 
cording to the marking at the top and bottom; the vertical, the 
temperature, as expressed on the left; on the dimbé are mariced 
the months, to which the several curves belong. 
By tracing the curve for January, it will be seen, that the mean 
temperature at 1, A. M. was above 19°, and slowly 
till 7, A. M., whence it rose rapidly till 2, P. M., and from 2 till 
midnight destined” again, rapidly between 4 and 6, the rest of 
the time slowly. It appears, therefore, that the maximum heat. 
of this mean January day, occurred about 2; P. M., and the min- 
imum about 7, A. M., the range being near 124°. The curves 
for the other months have the same general form. The maxi- 
mum is always near 2, P. M.; but the minimum, which com- 
monly takes place near sun-rise, varies from 4 to 8, A. M., accord- 
ing to the season. The heavy curve, commencing near 43° on 
the left, and marked “ year” on the right, exhibits the mean of 
all the other curves; and hence represents the thermometrical 
