Any good drawing of a whale shows at once how admirably these animals are fitted for gliding through the water (see Fig. 85). True, many of them have enormous heads, but these always have long face-bones ending in a rounded point, and even the huge head of the sperm whale (see Fig. 87), eighteen feet long, six feet high, and six feet wide, is rounded off above, and gradually thins away below, like the cutwater of a ship. The eyes are very tiny and so little exposed, that it is difficult to find them; there are no outer ears, though the bones within are large and probably very useful for hearing in water; the bones of the neck are seven, as is the rule among milk-givers, but they are so flattened and firmly soldered together, and so covered with blubber, that there is not even a hollow between the head and the body; while to crown all, the skin is perfectly smooth so as to offer no resistance to the water. Here, however, would be a disadvantage in the loss of the furry covering, since most of the whales travel into cold seas, were it not compensated by the great mass of oily fat or blubber which fills the cells in the under part of the skin, and keeps the whole body warm; and thus the whale, by a covering of fat often as much as a foot and a half thick, solves the problem of a warm-blooded animal, with a smooth gliding body, living in icy water without having its blood chilled. In every essential for swimming, then, whales are as well provided as any fish, while their immensely strong backbone, and the long cords or tendons running from the mass of muscle on the body to the tail, give them such tremendous power that a large whale makes nothing of tossing a whole boat’s crew into the air and breaking the boat in two. But, though they are so far true water-animals, yet they cannot live entirely below as fish can, for they have no apparatus for water-breathing. The outside of their body takes on the appearance of a fish, but inside they have the true lungs, the four-chambered heart, and all the complicated machinery of a warm-blooded animal. Therefore, though a whale may dive deep and remain below to seek its food, yet before an hour has passed even the largest of them must come floating up to the top again, to blow out the bad air through the nostrils at the top of the head, and fill the capacious lungs with a fresh supply. It is then that, partly because of the water which has run into the blowhole, and partly because the rush of breath throws up spray from the sea, we see those magnificent spouts of water which tell that a whale is below. The older naturalists thought that these spouts were caused by the water which the whale had taken into its mouth; but this is not so, and Scoresby, the great Arctic traveller, states distinctly that if the blowhole of the whale is out of the water only moist vapour rises with the breath, while when it makes a large spout this comes from its blowing under water and so throwing up a jet.