5 ^ 
Richards . — The Evolution of 
B. 
The experiments recorded in this section are comparisons 
of the temperature of two bell-glasses, properly packed with 
cotton wool, one containing the uninjured, the other the 
injured plants. The bell-glass containing the normal plants 
is always designated as bell-glass A, the other as bell-glass B. 
When it was desired to determine the ordinary plus tempera- 
ture shown in the bell-glass containing the uninjured objects, 
the other, usually bell-glass B, was filled with some substance 
to prevent the circulation of air, &c., and to render all the 
conditions as nearly equal as possible. Vessels containing 
KOH were always placed in the bell-glasses, and the objects 
supported above them. Formalin was employed to prevent 
the growth of fungi. The thermometers used were carefully 
compared, and found to be precisely alike and to agree with 
the standard thermometer. 
Experiment 21 . 
400 grams potatoes in each bell-glass. Had been kept in 
warm room two days before using. Injured by cutting into 
quarters. 
Duration of Experiment. 
Temp. Bell- 
Glass A. °C. 
Temp. Bell- 
Glass B. °C. 
Difference. 
Temperature 
outside. °C. 
Uninjured June i 
4.00 p.m. 
24.40 
24-40 
000 
24-00 
„ ,, 2 
9.00 a.m. 
24.15 
24.15 
0-00 
23.70 
Cut in quarters at 9.30 a.m. 
First day 
12.30 p.m. 
24.30 
24.40 
010 
23.90 
3-30 „ 
24.25 
24.60 
0.35 
23-60 
Second day 
6.30 „ 
24.25 
24*75 
0-50 
23.70 
1 1. 00 a.m. 
24.30 
25.IO 
0-80 
23.70 
,, 
1. 00 p.m. 
24.30 
25.20 
0-90 
23^5 
„ 
4.00 p.m. 
24*20 
24-95 
0-75 
23-60 
„ 
6.30 
24.25 
24.80 
0-65 
23.70 
Third day 
9.00 a.m. 
23*80 
24.30 
0-50 
23.40 
„ 
12.00 noon 
23.9° 
24-40 
0-50 
23.20 
„ 
3.00 p.m. 
23.90 
24.40 
0-50 
23.40 
,, 
6.00 „ 
24-00 
24-55 
0-55 
23.60 
Fourth day 
9.00 a.m. 
24.IO 
24.50 
0-40 
23.60 
Fifth day 
4.00 p.m. 
24.25 
24-60 
0-35 
23.70 
9.00 a.m. 
24.30 
24.65 
0-35 
23.80 
” 
5.00 p.m. 
24.30 
24.50 
0-20 
24-00 
