Vince seized him sharply by the shoulder, and Mike nearly fell back into the water; but this acted like a lever, and the boot was wrenched free, just as another whistle was heard and its answer, both sounding strangely near.
Quite certain that if they did not get in farther the reflection from the lanthorn must be seen, Vince waded on, with the water rising from his knees to his thighs, and then, feeling terribly cold, nearly to his waist.
“We mustn’t go any farther,” said Mike in an excited whisper, “or we shall have to swim.”
“Very well, then, we must swim,” said Vince, holding the light well up above the water, and looking anxiously along the dark channel ahead, the roof not being two feet above their caps.
Deeper still—the water above their waists—but the cavern went nearly straight on, and Vince was about to open the door and blow out the light, when Mike caught his arm.
“Don’t do that,” he whispered: “it would be horrible here, with those beasts about. There, you can hear one swimming, and we don’t know what else there may be.”
“But they’ll see the light.”
“Well, let them,” said Mike desperately. “I’d rather wade out.”
“I’ll risk it, then,” said Vince; and then he drew a breath of relief, for at the end of a couple of yards the depression along which they had passed was changing to a gradual rise of the cavern floor, and the water fell lower and lower, till it was considerably below their waists, and soon after shallow in the extreme.
They went on with mingled feelings, satisfied that they were getting where they would not be discovered, and also into shallow water, that promised soon to rise to dry land; but, on the other hand, they kept having hints that they were driving back living creatures, which made known their presence by wallowing splashes, that echoed strangely along the roof, and made the boys grasp club and cudgel with desperate energy.