THE FLIGHT ACTIVITIES OF THE HONEYBEE 
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3.15 to 3.45 A few drops are falling. 
3.45 to 4.00 Sprinkling. 
4.00 to 4.30 Steady shower falling. 
4.30 to 4.45 Sun shining brightly, though shower continues. 
5.00 Rain has stopped, bright sunshine. 
5.15 Again clouding over. 
5.45 A few drops falling. 
6.00 The sun is shining through the clouds for brief intervals. 
Although this day occurred between others of ^ood honey flow, 
the hive showed a loss in weight. An apparent gam in early after- 
noon was due to water on the hive. Each period of rain caused a 
decrease in flight, the heavy rain about noon causing the greatest 
decrease. In each case the bees resumed flight promptly with the 
slightest improvement of weather conditions. 
Fig. 7. — Flight, temperature, and hive-weight data for May 18, 1922, showing 
the effect on flight of an overcast day with occasional showers' 
THE EFFECT OF WIND 
Unfortunately for a thorough study of the effect of wind, there 
were few days during the period of these observations when the 
wind was strong enough to affect the flight appreciably. The in- 
formation is drawn from the records of only five days, and such 
statements as can be made on this subject are therefore made with 
some reservation. 
April 11 was a windy day, with no substantial honey flow. The 
successive numbers of exits increased with the rise in temperature 
until 8.30 a. m. During this period the velocity of the wind was 
only 4 to 5 miles per hour. Between 8.30 and 9 a. m. the wind 
velocity reached 10 miles per hour and the flight dropped and con- 
tinued low, while the velocity of the wind increased to 11 and 15 
miles per hour. At 2 p. m. the velocity fell to 6 miles per hour 
and later to 4 miles, with the flight responding by an increase, which 
no other observed factors woulcl explain. 
This record might suggest that a velocity of 10 miles per hour is 
the minimum velocity appreciably affecting flight. However, this 
can not be the case, for on April 10 a play flight took place, when 
