The question arises, how did those stones get into that field?
Three explanations are proposed.

One: that they are the products of former volcanic action; two: that they were brought from a distance by human agency; three: that they were carried thither from some distant country by icebergs.

Now each of those explanations involves certain consequences.

If the stones are volcanic, then they were once in a state of fusion.

But we find that they are unaltered limestone and contain fossils.