Page:Popular Science Monthly Volume 15.djvu/252

240 matter to trace the adaptation of the nostrils to the aquatic life and breathing habits of these animals.

There are natural history text-books still extant in which a very familiar error regarding the "blowing" of the whales is propagated—an error which, like many other delusions of popular kind, has become so fossilized, so to speak, that it is difficult to convince believers of its falsity. A manual of natural history, of no ancient date, lies before me as I write, and when I turn to the section which treats of the whales, I find an illustration of a Greenland whale, which is represented as lying high and dry on the beach, but which, despite its stranded state, appears in the act of vigorously puffing streams of water from the blowholes on the top of its head. To say the least of it, such an illustration is simply fictitious, and might safely be discarded as of purely inventive kind, were it only from the fact of its supposing a whale to be provided with some mysterious reservoir of water from which it could eject copious streams, even when removed from the sea. The common notion regarding the "blowing" of the whale appears to be that which credits the animal with inhaling large quantities of water into its mouth, presumably in the act of nutrition. This water was then said to escape into the nostrils and to be ejected therefrom in the act of blowing. The behavior of a whale in the open sea at first sight favors this apparently simple explanation. Careering along in the full exercise of its mighty powers, the huge body is seen to dive and to reappear some distance off at the surface, discharging from its nostrils a shower of water and spray. The observation is correct enough as it stands, but the interpretation of the phenomena is erroneous. Apart from the anatomical difficulties in the way of explaining how water from the mouth could escape in such large quantities, and so persistently into the nostrils, there is not merely an utter want of purpose in this view of the act of "spouting," but we have also to consider that this act would materially interfere with the breathing of the animal. Hence a more rational explanation of what is implied in the "blowing" of the whales rests on the simple assertion that the water and spray do not in reality proceed from the blowhole, but consist of water forced upward into the air by the expiratory effort of the animal. The whale begins the expiratory or "breathing-out" action of its lungs just before reaching the surface of the water, and the warm expired air therefore carries up with it the water lying above the head and blowholes of the ascending animal. That this view is correct is rendered highly probable, not merely by the observation of the breathing of young whales and porpoises kept in confinement, but also by the fact that the last portion of the "blow" consists of a white silvery spray or vapor, formed by the rapid condensation of the warm air from the lungs as it comes in contact with the colder atmosphere. The water received into the mouth escapes at the sides of the mouth, and does not enter the nostrils at all.