8 BULLETIN 988, U. S. DEPT. OF AGRICULTURE. 
RESULTS OBTAINED IN THE EXPERIMENT. 
Data indicating the physiological activity of the bees are sum- 
marized in the following table with others showing the experimental 
conditions. ,-° 
; Summary of experimental data. 
ca | Water 
Tae ag CO2in | Oxygen | vapor | Carbon | Oxygen | Heat 
Date. ae at Ain airin | in air in taken dioxid cog gener- 
chamber.| chamber. chamber.| chamber. noe e |produced.} sumed. ated. 
°C. | Percent. | Per cent.| Per cent.| Grams. | Liters. | Liters. | Calories. 
3 to 8.8 |...-...--- 0. 53 15.2 17.1 6 
.4to0 8.0) 75 to 90 1,42 16. 8 3.4 
.1t6 8.2} 77to0 90 . 87 17.1 5.0 
.3 to 7.0) 77t0 95 -81 21.1 8.1 
.3t07.6| 72 to 93 1. 08 22.6 8.3 
-8t09.2| 76 to 95 .52 24.5 6.9 
-1t0 7.8] 50 to 86 63 26.4 26. 5 
.9t07.9| 49 to 66 23 28.9 25.9 
8608.3) 47 to 66 1.40 24.5 22, 2 
4to07.7| 45 to 65 - 51 18.2 23, 2 
6 to 88) 50 to 55 29 7.3 15.9 
Dotal omitting frst day acu scewsesewemencunnmens vowmewaunasnwnennd 129.9 138, 4 683 
With the warm conditions prevailing in the laboratory, the cool- 
ing capacity of the apparatus, which had been constructed for work 
at higher temperatures, was not sufficient to chill the hive as much 
as had been desired when this experiment was planned, consequently 
the bees were not subjected to very low temperatures. Those shown 
in the table were measured with an electrical resistance thermometer 
suspended in the air above the hive, which was as warm as that in 
any part. of the apparatus, but the readings on two thermometers 
in other parts of the chamber did not differ materially from these. 
The figures shown are the lowest and highest temperatures observed 
each day, but there was no uniformity in the time at which these 
occurred. The fiuctuations in temperature are shown in the curve 
for thermocouple No. 15 on pages 15 to 18. The maximum range, 
from 6.1° to 9.2° C., was in the vicinity of the temperature which 
beekeepers usually consider favorable for bees wintering in cellars. 
The daily production of carbon dioxid shown in the table is an 
index of the amount of work performed by the bees. This quantity 
was derived, in the manner previously explained, from the weight 
of the carbon-dioxid absorber, which was taken every 24 hours. Any 
error in these figures, with the possible exception of those for Decem-’ 
ber 21 and 22, which are explained later, is believed to be of small 
magnitude. The most significant error that could occur. ‘would be 
due to the fact that the circulation of air was not directly through 
the hive, but through the chamber in which the hive was inclosed 
In some cases there might be an accumulation of carbon dioxid ta 
the hive in one period which would escape in a later period, with a 
