“Otter,” replied Uncle Andy, in a murmur as soft as the wind in the sedge-tops.

“Why?” continued the Babe, meaning to say—­“But what on earth are they doing?” and trusting that Uncle Andy would appreciate the self-restraint of the monosyllable.

“Sliding down hill,” muttered Uncle Andy, without turning his head.  Then, holding up his hand as a sign that there were to be no more questions asked, he crept forward noiselessly; and the Babe followed at his heels.

After two or three minutes the sounds were repeated in the same succession as before—­first two heavy splashes, and then two lighter ones.  Unable to ask questions, the Babe was obliged to think for himself.

He had only a vague idea what otters were like, but he knew a good deal about sliding down hill.  He pictured to himself a high, rough bank leading down to the water; but as not even Bill’s daring imagination would have represented the gamesome beasts as employing toboggans or hand-sleds, he thought it must be rather bumpy and uncomfortable work coasting over the roots and rocks on one’s own unprotected anatomy.

The sounds continued, growing louder and louder, till the two adventurers must have been within thirty or forty feet of the stream; and they were creeping as noiselessly as a shadow slips over the grass, in the hope of catching the merrymakers at their game.  But suddenly there came one great splash, heavy and prolonged, as if all the sliders had come down close together.  And then silence.  Uncle Andy crouched motionless for several minutes, as if he had been turned into a stump.  Then he straightened himself up with a disappointed air.

“Gone!” he muttered.  “Cleared out!  They’ve heard us or smelt us!”

“Oh!” exclaimed the Babe in a voice of deep concern; though, as a matter of fact, he was immensely relieved, the strain of the prolonged tension and preternatural stillness having begun to make him feel that he must make a noise or burst.

Two minutes later they came out on the banks of the stream.

The stream at this point was perhaps twenty-five feet in width, deep, dark, and almost without current.  Only by noting the bend of the long watergrasses could one tell which way it ran.  The hither bank was low and grassy, with a fallen trunk slanting out into the water.  But the shore opposite was some twelve or fifteen feet high, very steep, and quite naked, having been cut by the floods from a ridge of clay.  Down the middle of this incline a narrow track had been worn so smooth that it gleamed in the sun almost like ice.

As he stared across the water a dozen questions crowded to the Babe’s lips.  But he realized in time that the answers to them were fairly obvious to himself, and he heroically choked them back.  Had he not that very morning been rebuked by his uncle for asking too many of what he called “footy” questions?  But one burst forth now, in spite of himself.