This fine mountain rises nobly from the fertile Interval of the Connecticut, giving a character of boldness and majesty to scenery that were else merely soft and lovely. The river at this point broke down the barrier that evidently at one time held it back from the sea; and the broad lands that were then left bare by the liberated waters, were destined to form a strip of verdure and fertility, extending the whole length of New England. The expansions of the Valley of the Connecticut on either side of Mount Tom, are landscapes of great beauty. The word _interval_, which describes the wide-spreading meadows extending from the banks of the river in these expansions, has a peculiar use in America, and seems to define a formation of alluvial land not seen to the same extent in other countries. In the Southern States the same description of land is called a _flat_, or a _bottom_. They are formed by the deposit of particles of soil brought down into the main river by its tributaries, or by occasional streams created by the melting of the snow, or heavy rains. A shoal is first formed, which, as it accumulates, rises gradually above the ordinary surface, while the stream itself, if it flows like the Connecticut through a soft soil, is continually deepening its bed, and leaving these newly-formed banks out of the reach of accidental floods. The existence of some cause to check the current, is absolutely necessary to the formation of intervals. Wherever such cause is found, intervals are found proportioned to the room furnished on the side of the stream for their formation, and the lightness of the soil about the tributary streams. These causes exist on the Connecticut in falls and points of land, and in the narrowness of the channel at particular parts shut in by mountains. These lands are subject to many changes. Every new obliquity of the current wears away some part of the Interval, against which its force is directed. In the progress of such changes, the inhabitants of the Connecticut have already seen large tracts gradually removed from one side to the other. The former channel in the mean time has been filled up, so as, in many instances, to leave no trace of its existence, and a new one has been made through the solid ground.