THE TEMPERATURE OF LEAVES OF PINUS IN WINTER 
57 
Table VIII 
January 25, 191 4 
Approximately one half full sunshine. Light breeze. Relative humidity 78.5% 
I 
2 
3 
4 
5 
6 
7 
8 
9 
945 
22.5 
2.77°' 
-5-73 
947 
21.5 
2.65 
16.7° 
-5-85 
9.48 
20.3 
2.50 
-8.5° 
25.2% 
— 6.00 
1.2 
949 
20.0 
2.46 
— 6.04 
9-50 
257 
3-17 
-5-33 
9-53 
26.8 
3-30 J 
-5-20 ^ 
II. 10 
26.9 
3-31 ' 
-4.69 ^ 
II. II 
33-7 
4.14 
-3.86 
II. 12 
36.3 
4.46 
-8.0 
20.0 
28.0 ^ 
-3-54 
0.8 
II. 15 
36.3 
4.46 
-3-54 
11.20 
32.5 
3-99 
-4.01 
11.22 
36.7 
4-51 - 
-3.59 . 
Average 
347 
-8.25 
26.6 
-4.78 
Table IX 
February 2, IQ14 
Approximately one fourth full sunshine. Breeze moderately strong. Relative 
humidity 83.5% 
I 
3 
4 
5 
6 
7 
8 
9 
Time of 
Observa- 
tion 
No. of 
Obser- 
vations 
Aver. 
Bridge 
Reading 
in Cm. 
Calculated 
Temp. 
Diff. 
Shade 
Temp. 
Black Bulb 
in Vacuum 
Difference 
Columns 
5 and 6 
Actual 
Leaf 
Temp. 
Wind 
Velocity 
Miles 
per Hr. 
10.34 
10.40 
11.00 
II. 15 
11.46 
11-55 
12.36 
1.25 
1-31 
2.34 
I 
5 
4 
5 
5 
3 
3 
3 
4 
3 
24.8 
14-5 
14.0 
11.5 
13-5 
16.1 
10.9 
18.9 
21.5 
II.O 
3.00° 
1-75 
1.69 
1-39 
1.63 
1.94 
1.31 
2.27 
2.58 
1-39 
— 1.0° 
-0.8 
-0.5 
0 
0 
0.2 
I.O 
1.8 
2.0 
2-5 
20.0° 
22.2 
22.2 
17.8 
18.3 
19.2 
16.7 
19.7 
22.2 
19.4 
21.0° 
23.0 
22.7 
17.8 
18.3 
19.0 
15-7 
17.9 
20.2 
16.9 
2.00° 
.95 
1. 19 
1-39 
1-63 
2.14 
2.31 
4.07 
4-58 
3-89 
4-8 
4.8 
4.8 
4-8 
3-7 
3-2 
3-6 
3-6 
3-6 
1 Average 
1.89 
0.52 
19-25 
2.41 
With approximately one fourth of full sunlight, and with a light 
breeze blowing, the maximum differential temperature obtained was 
3.18° C. and the average 2.17° C. (Table VII); with approximately 
the same radiation (compare column 7, Tables VII and IX) and a 
moderate breeze blowing, the maximum is 3.0° C. and the average 
only 1.89° C; with approximately one half of full sunlight (Table VII) 
