Land Formerly Covered with Water. I asked Mr. Benjamin Franklin and other gentlemen who were well acquainted with this country, whether they had come upon any evidence that places which were now a part of the continent had formerly been covered with water; and I received the following answer.

1. On travelling from here to the south, you meet with a place where the highway is very low in the valley between two mountains. On both sides you see nothing but oyster and mussel shells in immense quantities. Yet the place is many miles from the sea.

2. Whenever colonists dig wells or build houses in town, they find the earth lying in several strata above each other. At a depth of fourteen feet or more they find globular stones, which are as smooth on the outside as those which lie on the seashore and have been made round by the rolling of the waves. After having dug through the sand and reached a depth of eighteen feet or more they discovered in some places a mud like that which the sea throws up on the shore, and which commonly lies at its bottom and in rivers; this mud is full of stumps, leaves, branches, reed, charcoal, etc.

3. It has sometimes happened that new houses have sunk on one side in a short time, and have obliged the people to pull them down again. On digging deeper for hard ground to build upon they have found a quantity of the above mud, wood, roots, etc.

Are not these reasons sufficient to make one suppose that those places in Philadelphia which are at present fourteen feet and more under ground were formerly the bottom of the sea, and that by several violent changes, sand, earth, and other things were carried upon them? or, that the Delaware formerly was broader than it is at present? or that it has changed its course? This last still happens at present, the river tearing off material from the bank on one side, and depositing it on the other. Both the Swedes and English often showed me such places.