“First of all, every precaution is taken to avoid all loss, all unnecessary expenditure of heat, and to economize as much as possible the reserves of fuel in their poor little veins. The hedgehog wraps itself up warm in a thick blanket of leaves in the heart of a stone-heap or in some hollow tree trunk, while the bats collect in compact groups in the warm shelter of a deep cave. But that is not enough: they must keep quite still, as every movement uses up a certain amount of heat. This requirement is scrupulously observed: their immobility is such that you would say they were dead. And yet all this is still insufficient: respiration must be reduced to a minimum. In fact, their breathing is so weak that the closest scrutiny can hardly detect that they breathe at all. This faint remnant of life is not to be compared, you can well see, to the blazing torch or the brightly burning fire, both of which, enjoying free combustion, send out waves of heat and light. It is rather the feeble glimmer of a night lamp husbanding its last drop of oil; it is the coal that glows faintly under the ashes. So profound is the torpor, so nearly complete the inanition, that were it not followed by an awakening this state would hardly differ in any respect from death. “The name ‘hibernation’ is given to this temporary suspension of vitality, or rather this slowing up of life, to which certain animals are subject during the winter. In the number of hibernating animals, or animals that indulge in this long winter sleep, are to be included, besides the hedgehog and the bat, the marmot, the dormouse, the lizard, serpents of various kinds, frogs, and other reptiles. Do you need to be told that in order to assume and maintain this torpid condition in which for whole months food is unnecessary, a special organization is required? Not every creature can hold its breath at will and thus escape the necessity of eating. The dog and the cat might sleep ever so deeply, yet as their breathing would go on almost as actively as in their waking hours, hunger would arouse them before long.” “Just as it would me,” said Emile. “No animals that have an assured supply of food for the winter hibernate, but those that would otherwise perish with hunger in cold weather are saved from destruction by the providential torpor that overtakes them at the approach of the winter season. Their food supply being cut off, they go to sleep. The marmot is wrapped in slumber while the turf on the high mountains is covered with snow; the dormouse when there is no longer any fruit; frogs, toads, snakes, lizards, bats, and hedgehogs, as soon as there cease to be any more insects to feed upon.” CHAPTER IX THE MOLE