214 Connecticut River Valley. 
IV. Auziouviat Formations. 
Plains and meadows.—The surface of the shallow covering of earth 
upon hills and mountains, presents the form and pressure of the rock 
beneath. The earth lies mingled without apparent order or uniformity 
of arrangement. But in the valleys of the tributary streams, and on 
a larger scale in the central valley of the Connecticut, long continued 
accumulations have formed extensive plains and meadows, the pro- 
duct of alluvial deposition and subsidence. Such plains and mea- 
dows are found at Lancaster, N. H. Along the Fifteen mile falls, 
hills press more closely upon the river, alternately diminishing and 
excluding alluvial formation. Below the Fifteen mile falls the hills 
recede, and admit the broad meadows of the great and little ox-bow, 
and the plains of Haverhill and Newbury. At White river falls, 
thirty miles lower, and at several intermediate points, rocky spurs 
close upon the river, which proceeds to its mouth through alternate 
meadows, plains, and hills. 
In common language, the higher alluvial is called plain ; the low- 
m particularly when within the reach of inundations from 
the river. The similarity of their external appearance and internal 
arrangement indicate that they have been formed by similar causes, 
throughout the whole length of the valley. 
Arranged in terraces.—The plains and meadows are generally so lev- 
el, that their declination is not perceived by the eye. Three distinct 
terraces of plain and meadow, in some portions of the valley four, rise 
to various heights, from fifteen or twenty to two hundred feet, above 
the surface of the Connecticut. ‘The upper terrace of plains extends 
to the hills whether near or distant, and rests against their sides. The 
faces of plains towards the river are generally formed into sweeping 
curves, and slope with a regular descent, to the level next below- 
Some of the plains may be traced from one great fall in the river to 
another, twenty or thirty miles, disappearing where projecting spurs 
or other local causes prevented their formation, or the subsequent 
action of the river undermined and removed them. A spectator 
standing on the upper plain, and looking across the river, may com- 
monly see portions of a similar plain, of corresponding height, ter- 
Minating against’ the opposite bill sides. The angle at the brow o} 
the plains, and the steep and regular descent down their faces, 
31 not the same in all, are perfectly distinguishable from the 
and curving slopes of hills and mountains. The lower plains 
