Henry David Thoreau: Walden

16. The Pond in Winter (continued)

A factory-owner, hearing what depth I had found, thought that it could not be true, for, judging from his acquaintance with dams, sand would not lie at so steep an angle. But the deepest ponds are not so deep in proportion to their area as most suppose, and, if drained, would not leave very remarkable valleys. They are not like cups between the hills; for this one, which is so unusually deep for its area, appears in a vertical section through its centre not deeper than a shallow plate. Most ponds, emptied, would leave a meadow no more hollow than we frequently see. William Gilpin, who is so admirable in all that relates to landscapes, and usually so correct, standing at the head of Loch Fyne, in Scotland, which he describes as "a bay of salt water, sixty or seventy fathoms deep, four miles in breadth," and about fifty miles long, surrounded by mountains, observes, "If we could have seen it immediately after the diluvian crash, or whatever convulsion of nature occasioned it, before the waters gushed in, what a horrid chasm must it have appeared!

             "So high as heaved the tumid hills, so low
              Down sunk a hollow bottom broad and deep,
              Capacious bed of waters."

But if, using the shortest diameter of Loch Fyne, we apply these proportions to Walden, which, as we have seen, appears already in a vertical section only like a shallow plate, it will appear four times as shallow. So much for the increased horrors of the chasm of Loch Fyne when emptied. No doubt many a smiling valley with its stretching cornfields occupies exactly such a "horrid chasm," from which the waters have receded, though it requires the insight and the far sight of the geologist to convince the unsuspecting inhabitants of this fact. Often an inquisitive eye may detect the shores of a primitive lake in the low horizon hills, and no subsequent elevation of the plain have been necessary to conceal their history. But it is easiest, as they who work on the highways know, to find the hollows by the puddles after a shower. The amount of it is, the imagination give it the least license, dives deeper and soars higher than Nature goes. So, probably, the depth of the ocean will be found to be very inconsiderable compared with its breadth.