The whole question is to know whether the water covers the ant-hill or not.

If we make a small opening at the summit of the cone, we shall find out which it is.

But in case the ant-hill should be submerged now, the water would fill it entirely, and we would be lost.

Let us feel our way." "But quickly," replied Tom.
In fact, the level continued to rise gradually.

There were then six feet of water inside the cone.