When there are no young bees, the old bees will act as house-keepers and nurses, which they otherwise refuse to do. The young bees, on the other hand, will not go forth to glean, even though there be no old bees to do this necessary part of bee-duties. An indirect function of all the bees is to supply animal heat, as the very life of the bees require that the temperature inside the hive be maintained at a rate considerably above freezing. In the chemical processes attendant upon nutrition, much heat is generated, which, as first shown by Newport, may be considerably augmented at the pleasure of the bees, by forced respiration. The bees, too, by a rapid vibration of their wings, have the power to ventilate their hives, and thus reduce the temperature, when the weather is hot. Thus they moderate the heat of summer, and temper the cold of winter. [Illustration: _Under Surface of Bee, showing Wax between Segments._] CHAPTER III. SWARMING OR NATURAL METHOD OF INCREASE. The natural method by which an increase of colonies among bees is secured, is of great interest, and though it has been closely observed, and assiduously studied for a long period, and has given rise to theories as often absurd as sound, yet, even now, it is a fertile field for investigation, and will repay any who may come with the true spirit of inquiry, for there is much concerning it which is involved in mystery. Why do bees swarm at unseemly times? Why is the swarming spirit so excessive at times and so restrained at other seasons? These and other questions we are too apt to refer to erratic tendencies of the bees, when there is no question but that they follow naturally upon certain conditions, perhaps intricate and obscure, which it is the province of the investigator to discover. Who shall be first to unfold the principles which govern these, as all other actions of the bees?