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1A factory owner, hearing what depth I had found, thought that it could not be true, for, judging from his acquaintance
2with dams, sand would not lie at so steep an angle. But the deepest ponds are not so deep in proportion to their area as
3most suppose, and, if drained, would not leave very remarkable valleys. They are not like cups between the hills; for
4this one, which is so unusually deep for its area, appears in a vertical section through its centre not deeper than a
5shallow plate. Most ponds, emptied, would leave a meadow no more hollow than we frequently see. William Gilpin, who is
6so admirable in all that relates to landscapes, and usually so correct, standing at the head of Loch Fyne, in Scotland,
7which he describes as "a bay of salt water, sixty or seventy fathoms deep, four miles in breadth," and about fifty miles
8long, surrounded by mountains, observes, "If we could have seen it immediately after the diluvian crash, or whatever
9convulsion of Nature occasioned it, before the waters gushed in, what a horrid chasm must it have appeared! So high as
10heaved the tumid hills, so low Down sunk a hollow bottom broad and deep, Capacious bed of waters--." But if, using the
11shortest diameter of Loch Fyne, we apply these proportions to Walden, which, as we have seen, appears already in a
12vertical section only like a shallow plate, it will appear four times as shallow. So much for the increased horrors of
13the chasm of Loch Fyne when emptied. No doubt many a smiling valley with its stretching cornfields occupies exactly such
14a "horrid chasm," from which the waters have receded, though it requires the insight and the far sight of the geologist
15to convince the unsuspecting inhabitants of this fact. Often an inquisitive eye may detect the shores of a primitive
16lake in the low horizon hills, and no subsequent elevation of the plain has been necessary to conceal their history. But
17it is easiest, as they who work on the highways know, to find the hollows by the puddles after a shower. The amount of
18it is, the imagination give it the least license, dives deeper and soars higher than Nature goes. So, probably, the
19depth of the ocean will be found to be very inconsiderable compared with its breadth. As I sounded through the ice I
20could determine the shape of the bottom with greater accuracy than is possible in surveying harbors which do not freeze
21over, and I was surprised at its general regularity. In the deepest part there are several acres more level than almost
22any field which is exposed to the sun wind and plough. In one instance, on a line arbitrarily chosen, the depth did not
23vary more than one foot in thirty rods; and generally, near the middle, I could calculate the variation for each one
24hundred feet in any direction beforehand within three or four inches. Some are accustomed to speak of deep and dangerous
25holes even in quiet sandy ponds like this, but the effect of water under these circumstances is to level all
26inequalities. The regularity of the bottom and its conformity to the shores and the range of the neighboring hills were
27so perfect that a distant promontory betrayed itself in the soundings quite across the pond, and its direction could be
28determined by observing the opposite shore. Cape becomes bar, and plain shoal, and valley and gorge deep water and
29channel. When I had mapped the pond by the scale of ten rods to an inch, and put down the soundings, more than a hundred
30in all, I observed this remarkable coincidence. Having noticed that the number indicating the greatest depth was
31apparently in the centre of the map, I laid a rule on the map lengthwise, and then breadthwise, and found, to my
32surprise, that the line of greatest length intersected the line of greatest breadth exactly at the point of greatest
33depth, notwithstanding that the middle is so nearly level, the outline of the pond far from regular, and the extreme
34length and breadth were got by measuring into the coves; and I said to myself, Who knows but this hint would conduct to
35the deepest part of the ocean as well as of a pond or puddle? Is not this the rule also for the height of mountains,
36regarded as the opposite of valleys? We know that a hill is not highest at its narrowest part. Of five coves, three, or
37all which had been sounded, were observed to have a bar quite across their mouths and deeper water within, so that the
38bay tended to be an expansion of water within the land not only horizontally but vertically, and to form a basin or
39independent pond, the direction of the two capes showing the course of the bar. Every harbor on the sea-coast, also, has
40its bar at its entrance. In proportion as the mouth of the cove was wider compared with its length, the water over the
41bar was deeper compared with that in the basin. Given, then, the length and breadth of the cove, and the character of
42the surrounding shore, and you have almost elements enough to make out a formula for all cases. In order to see how
43nearly I could guess, with this experience, at the deepest point in a pond, by observing the outlines of its surface and
44the character of its shores alone, I made a plan of White Pond, which contains about forty-one acres, and, like this,
45has no island in it, nor any visible inlet or outlet; and as the line of greatest breadth fell very near the line of
46least breadth, where two opposite capes approached each other and two opposite bays receded, I ventured to mark a point
47a short distance from the latter line, but still on the line of greatest length, as the deepest. The deepest part was
48found to be within one hundred feet of this, still farther in the direction to which I had inclined, and was only one
49foot deeper, namely, sixty feet. Of course, a stream running through, or an island in the pond, would make the problem
50much more complicated. If we knew all the laws of Nature, we should need only one fact, or the description of one actual
51phenomenon, to infer all the particular results at that point. Now we know only a few laws, and our result is vitiated,
52not, of course, by any confusion or irregularity in Nature, but by our ignorance of essential elements in the
53calculation. Our notions of law and harmony are commonly confined to those instances which we detect; but the harmony
54which results from a far greater number of seemingly conflicting, but really concurring, laws, which we have not
55detected, is still more wonderful. The particular laws are as our points of view, as, to the traveller, a mountain
56outline varies with every step, and it has an infinite number of profiles, though absolutely but one form. Even when
57cleft or bored through it is not comprehended in its entireness.
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