"I suppose we must be going east." "Well, then, if you started by going east, and kept on rowing till you are going east again, I think you may conclude that you have gone nearly round a piece of land, and that the said piece is an island.

It might not be, for we may be going right into some gulf; but this place looks as much like an island as is possible, and I don't think it can be anything else." "Island," said Gregory, gruffly, "volcanic, and the coral has risen up round it, and kept it from being washed away." "But could an island like this have been washed away ?" said Mark.
"To be sure it could, my boy," said the captain.

"From what I have seen a great deal of it is loose scoria.

You saw plenty of big stones lying about ?" "Yes," replied Mark, "but they were huge stones.

Some of them must weigh half a ton." Mark knew that half a ton meant ten hundredweight; but his comparison was a shot at a venture, for he had no idea how big, or rather how small, a rock is which weighs half a ton.
"I don't think the sea would make much of a rock weighing half a ton, Mark," said the captain, smiling.