Presently, old Tom pointed out that the height of the water was gradually increasing, but only by very slow ascent. Dick could only say that if the flood continued to rise, however slowly, it must inevitably drive out the air.
As if struck by a sudden thought, Bat called out,-
"Let me try and get outside. Perhaps I might dive and get through the opening."
"I think I had better make that experiment myself," answered Dick.
"That you never shall," interposed Tom peremptorily; "you must let Bat go. It may not be possible to get back, and your presence is indispensable here. Think, sir, think of Mrs. Weldon, and Master Jack," he added in a lower tone.
"Well, well," Dick assented, "if it must be so, Bat shall go."
And turning to Bat, he continued,
"Do not try to come back again; we will try, if we can, to follow you the same way; but if the top of the cone is still above water, knock hard on it with your hatchet, and we shall take it as a signal that we may break our way out. Do you understand?"
"All right!" he said, "all right, sir."
And after wringing his father's hand, he drew a long breath, and plunged into the water that filled the lower section of the ant-hill.