The whale was usually first sighted by the lookout in the crow's nest. A warm-blooded animal, breathing with lungs, and not with gills, like a fish, the whale is obliged to come to the surface of the water periodically to breathe. As he does so he exhales the air from his lungs through blow-holes or spiracles at the top of his head; and this warm, moist air, coming thus from his lungs into the cool air, condenses, forming a jet of vapor looking like a fountain, though there is, in fact, no spout of water. "There she blows! B-l-o-o-o-ws! Blo-o-ows!" cries the lookout at this spectacle. All is activity at once on deck, the captain calling to the lookout for the direction and character of the "pod" or school. The sperm whale throws his spout forward at an angle, instead of perpendicularly into the air, and hence is easily distinguished from right whales at a distance. The ship is then headed toward the game, coming to about a mile away. As the whale, unless alarmed, seldom swims more than two and a half miles an hour, and usually stays below only about forty-five minutes at a time, there is little difficulty in overhauling him. Then the boats are launched, the captain and a sufficient number of men staying with the ship. [Illustration: "THERE SHE BLOWS"] In approaching the whale, every effort is made to come up to him at the point of least danger. This point is determined partly by the lines of the whale's vision, partly by his methods of defense. The right whale can only see dead ahead, and his one weapon is his tail, which gigantic fin, weighing several tons and measuring sometimes twenty feet across the tips of the flukes, he swings with irresistible force and all the agility of a fencer at sword-play. He, therefore, is attacked from the side, well toward his jaws. The sperm whale, however, is dangerous at both ends. His tail, though less elastic than that of the right whale, can deal a prodigious up-and-down blow, while his gigantic jaws, well garnished with sharp teeth, and capacious gullet, that readily could gulp down a man, are his chief terrors. His eyes, too, set obliquely, enable him to command the sea at all points save dead ahead, and it is accordingly from this point that the fishermen approach him. But however stealthily they move, the opportunities for disappointment are many. Big as he is, the whale is not sluggish. In an instant he may sink bodily from sight; or, throwing his flukes high in air, "sound," to be seen no more; or, casting himself bodily on the boat, blot it out of existence; or, taking it in his jaws, carry it down with him. But supposing the whale to be oblivious of its approach, the boat comes as near as seems safe, and the harpooner, poised in the bow, his knee against the bracket that steadies him, lets fly his weapon; and, hit or miss, follows it up at once with a second bent onto the same line. Some harpooners were of such strength and skill that they could hurl their irons as far as four or five fathoms.