I am not sure if the winter sleep of the polar bear is a heavy or a light one, or whether the Esquimaux, who live in these arctic regions, are bold enough to interfere with it if they happen to come upon its sleeping-place. The brown bear of Siberia, however, is sometimes attacked whilst hibernating, and this is a very dangerous thing to do, for this species—unlike the black bear of America—sleeps lightly, and is very fierce when disturbed. The way employed is for one man to descend into the bear’s cave, at the end of a rope, the other end being held by two or three men, who stand at the cave’s mouth. The man who goes in has a torch, or a candle, fixed into his cap—at least I think I have somewhere read this account—so that he can both see before him, and carry his gun in both hands. When he sees the bear lying asleep he creeps cautiously up, and putting the muzzle of his gun against the side of the animal’s head, pulls the trigger. As soon as the men outside hear the roar of the gun in the cave, they pull on the rope, and the assassin starts running at the same time. If he stumbles or falls, he is pulled along the ground, and in this way may avoid the rush of the bear, supposing the shot has not killed it. If the muzzle of the gun has been well placed, it ought, of course, to be a certain thing, but the bear may wake first, or move just at the critical moment, or it may be difficult, in the dark cavern, only dimly illumined by the flickering light of the candle, to see in what position it is lying. All this has to be risked. Still, on the whole, the chances are a good deal against the bear, and if its cavern—or hibernaculum, to use the technical word—is once found, it is pretty sure to be killed, even though it may, sometimes, kill a man or two first. I forget, now, exactly where I have read this account, but it was in a trustworthy book, I feel sure, so I hope it is correct in the main, even though I may have forgotten some of the particulars. Bears are the largest animals that hibernate, unless some very big crocodiles or alligators may be considered to be larger still; and, perhaps, as these giants attain a length of twenty or even thirty feet, they may weigh as much or more. These creatures generally sleep in holes under the river-bank, but the alligator of tropical America will, sometimes, bury itself in the mud of a swamp, which may then dry up altogether, so that an encampment, or even a hut, may be raised upon it. In time the rains fall, the ground begins to grow moist again, and someone lying in his hammock, or just sitting down to breakfast, may be startled, all at once, by a great alligator rising up beneath him, out of the mud that makes the floor of his hut.