!I74 



THE MUSEUM. 



Voluta imperialis, East Indies. A rare species; hard to secure. 



tory of an important geological change 

 is recorded; and so plainly is it written, 

 that even the most casual observer 

 cannot fail to notice and read, at least 

 -a portion of it. 



About forty miles from the mouth of 

 the river, its valley is crossed, nearly 

 at right angles, by a spur of the Green 

 ^Mountains, which, branching from the 

 main range, extends in a more north- 

 •erly direction. This range, where it 

 •crosses the Winooski valley, is not far 

 from two thousand feet in height; but 

 it is cleft by a chasm, the result of a 

 fracture during a geological upheaval, 

 which extends to a level with the val- 

 ley, and through which the river finds 

 an easy passage. Here, at the foot of 

 the mountains, upon the east side, and 

 partially in the chasm, and upon the 

 right bank of the river, is the little vil- 

 lage of Middlesex. 



Opposite this village, which contains 

 perhaps, one hundred and fifty inhabi- 

 tants, the river, for a distance of eighty 

 rods, flows over a naked ledge of slate- 

 stone into which it has worn a channel 

 in places more than fifty feet in depth, 

 and of a sufficient width to admit of 

 the tolerably free passage of the 



stream. This channel, it is plain to 

 be seen, is the result of erosion; and 

 obviously, before its excavation, the 

 ledge through which it is cut, must 

 have formed a barrier across the river, 

 the result of which must have been to 

 form a lake above, and a cataract, or 

 at least, a series of falls below. The 

 topography of the surrounding country 

 is such that no other conclusion is pos- 

 sible. 



In looking for traces of this lake we 

 find, about a mile above the village, 

 and on the left bank of the river, a 

 mountain spur, jutting out towards the 

 river in such a manner as to have 

 formed a huge promontory in the lake. 

 Here, upon close examination, we 

 find horizontal grooves cut into the 

 .soft slate rock of which the mountain 

 is composed. Evidently they were 

 made by the waves of the old lake. 

 Above these wave lines, the soil which 

 thinly covers portions of the almost 

 perpendicular side of the mountain, is 

 of a different nature from that of ad- 

 jacent localities. It contains very lit- 

 tle of the original drift, but is com- 

 posed of disintegrated and pulverized 

 slate stone mixed with such materials 



