When he was old enough to stop drinking milk he learned to eat the food which his mother liked. He often watched her swimming around the bay, with her great mouth hanging open. There were millions of the tiniest kind of creatures living in the water. They flowed into her mouth at the same time with the water. When she felt them tickling and wiggling over her tongue she closed her jaw almost shut. A sieve of long elastic strips of bone fell like a curtain from the roof of her mouth. Then the water drained out between the strips of bone, leaving the tiny animals inside to be swallowed.
Instead of teeth the baby whale found such a fringe of whalebone strips growing on the roof of his mouth. When it was long enough to use he began to swim around with his jaw hanging down. Every day, in this way, he caught and ate thousands of tiny shrimps and crabs and mussels. He could not swallow any large fish because his throat was only a few inches wide.
He did not know that there are different whales in a different part of the sea. These other whales have teeth instead of whalebone sieves. In the tops of their heads they have great holes filled with sperm oil. Their throats are wide enough to swallow a man. They are called sperm whales, but the whales with whalebone strips in their mouths are called true whales.
When the baby stopped drinking milk the mother set out with him to leave the bay, and find the father whale in the deep sea without. The young whale could swim almost as fast as the old one now. He could stay under water without breathing quite as long as she could. The warm blanket of blubber under his skin had grown thicker. It kept him warm and helped him to float.
Perhaps he was afraid to leave the safe bay for the wide ocean. He kept close beside his mother as they went rushing on, with their tails slapping up and down and around. The tail sent each one ahead, just as the screw of a steamer drives it forward. With their flippers they steadied their round bodies so that they would not roll over and over like logs.
Out between the rocky cliffs, at the mouth of the inlet, they rushed through the green water. After travelling some distance out to sea the baby noticed that the water looked black below them, reaching down and down and down. He could not see the oozy, shell-covered floor, as in the bay. Above him the waves were larger, and swayed to and fro, cresting in foam. The big fishes were darting hither and thither before the great round, rushing bodies of the mother and the baby whale.
Very likely the old whale had been lonesome in the bay. She swam on in a hurry to find her mate and the rest of the herd. The baby followed as hard as he could paddle. This was a wonderful new world to him. Probably he wanted to stop and look around, especially when he rose to breathe. Once he gave a mighty jump and shot out far above the waves. He could not see well, except directly behind him. But while above there in the air he twisted in a curving leap. Everywhere water, water, water, stretching on and on and on.
He could not see a single sign of any other whales being near. Yet somehow or other the old mother knew that they were not far away. It may be that she could hear through the water, as if telephone-wires were spread under the waves. Sure enough! soon the baby heard the splashing of heavy bodies turning over and over in slow rolling. When he rose to breathe he caught sight of spouting fountains, where the other whales were blowing in the sea.