39% PERFECT SOCIETIES OF INSECTS. 
placed very near each other, are perpendicular to the abdomen, so as to 
give that part considerable elevation. 
Maraldi, and after him Reaumur, long ago noticed this action of the 
bees; but they attributed to it an effect the reverse of that which it really 
produces ; the former imagining it to occasion directly the high tempe- 
rature of the hive, and the latter indirectly.! It was reserved for Huber 
to discover the true cause of it ; and from him the chief of what I haye 
to say upon the subject will be derived.” 
During the summer a certain number of workers— for it is to the 
workers solely that this office is committed —may always be observed 
vibrating their wings before the entrance of their hive ; and the observant 
apiarist will find, upon examination, that a still greater number are engaged 
within it in the same employment. All those thus circumstanced that 
stand without turn their head to the entrance; while those that stand 
within turn their back to it. The station of these ventilators is upon the 
floor of the hive, They are usually ranged in files that terminate at the 
entrance ; and sometimes, but not constantly, form so many diverging 
rays, probably to give room for comers and goers to pass. The number 
of ventilators in action at the same time varies: it seldom much exceeds 
twenty, and is often more circumscribed. The time also that they devote 
to this function is longer or shorter, according to circumstances: some 
have been observed to continue their vibrations for nearly half an hour 
without resting, suspending the action for not more than an instant, as 
it should seem to take breath. When one retires, another occupies 
its place; so that in a hive well peopled there is never any interruption 
of the sound or humming occasioned by this action, by which it may 
always be known whether it be going on or not. 
This humming is observable not only during the heats of summer, but 
at all seasons of the year. It sometimes seems even more forcible in 
the depth of winter than when the temperature of the atmosphere is 
higher. An employment so constant, which always occupies a certain 
number of bees, must produce as constant an effect. The column of air 
once disturbed within must give place to that without the hive; thus a 
current being established, the ventilation will be perpetual and complete. 
To be convinced that such an effect is produced, approach your hand 
to a ventilating bee, and you will find that she causes a very perceptible 
motion in the air. Huber tried an experiment still more satisfactory. 
Cn a calm day, at the time when the bees had returned to their habitation 
— having fixed a screen before the mouth of the hive to prevent his being 
misled by any sudden motion of the external air —he placed within the 
screen little anemometers or wind-gauges, made of bits of paper, feather, 
or cotton, suspended by a thread to a crotch. No sooner did they enter 
the atmosphere of the bees than they were put in motion, being alter- 
nately attracted and repelled to and from the aperture of the hive with 
considerable rapidity. These attractions and repulsions were propor- 
tioned to the number of bees engaged in ventilation, and though some- 
times less perceptible, were never entirely suspended. Burnens tried 4 
similar experiment in the winter, when the thermometer stood in the 
shade at 33°. Having selected a well-peopled hive, the inhabitants of 
which appeared full of life and sufficiently active in the interior, and luted 
1 Reaum, y. 672. 2 Huber, ii. 888—362. 
