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.