VENTILATION OF THE BEE-HIVE. 177 
is forced out. By a series of beautiful experiments, Huber 
ascertained that the air of a crowded hive is almost as pure 
as the surrounding atmosphere. Now, as the entrance to 
such a hive is often very small, the air within cannot be 
renewed, without resort to artificial means. If a lamp is 
put into a close vessel, with only one small orifice, it will 
soon exhaust the oxygen, and cease to burn. If another 
small orifice is made, the same result will follow; butif a 
current of air is by some device drawn out from one open- 
ing, an equal current will force its way into the other, and 
the lamp will burn until the oil is exhausted. 
365. It is on this principle of maintaining a double cur- 
rent by artificial means, that bees ventilate their crowded 
habitations. A file of ventilating bees stands inside and 
outside of the hive, each with head turned to its entrance, 
and while, by the rapid fanning of their ‘‘ many twinkling’”’ 
wings, a brisk current of air is blown out of the hive, an 
equal current is drawn in. As this important office demands 
unusual physical exertion, the exhausted laborers are, from 
time to time, relieved by fresh detachments. If the interior 
of the hive permits inspection, many ventilators will be 
found scattered through it, in very hot weather, all busily 
engaged in their laborious employment. If its entrance is 
contracted, speedy accessions will be made to their num- 
bers, both inside and outside of the hive; and if it is closed 
entirely, the heat and impurity quickly increasing, the 
whole colony will attempt to renew the air by rapidly vi- 
brating their wings, and in a short time, if unrelieved, will 
die of suffocation. 
366. Careful experiments show that pure air is neces- 
sary not only for the respiration of the mature bees, but for 
hatching the eggs, and developing the larve; a fine netting 
of air-vesgels enveloping the eggs, and the cells of the larvee 
being closed with a covering filled with air-holes (168). 
In Winter, if bees are kept ina dark place, which is 
12 
