Now the gaps are very wide, as some of the buffaloes are lagging behind; and some are turning too much to the side in trying to reach a mouthful from a shrub or a bush here and there.

Why, what is happening now? Some of the buffaloes cannot even see one another now, because of the bushes between them! What are the sentinels doing? And what is the leader doing? Suppose a tiger suddenly comes—

But do you hear that?

"Moo! Moo!"

That is the leader. He has just found out that the herd is spread out too far; so he is calling. He is saying, "Where are you?"

"Moo! Moo!" Do you hear that answer? It comes from the sentinel on the right, who is very far away now; but still he has heard the call. His answer means, "Here I am!"

And "Here I am!" comes the answer also from the sentinel on the left.

"Then close up!" cries the leader.

Each sentinel moves up toward the place from which he heard the leader's voice come. And on his way there he tells all the buffaloes he meets to move up also. Besides, all the buffaloes hear the leader's voice too; so they begin to close up at once.

Is not that a wonderful way of bringing up all those that are lagging behind?