IN MASSACHUSETTS AND VERMONT. 139 



junction of the east and west branches, at Chester village and Chester Factories, 

 which are a little more than six miles higher up the stream. It passes over this 

 distance almost at right angles across nearly perpendicular strata of mica slate, 

 portions of which project occasionally, so as to form prominent objects against which 

 a force pressing down the valley must have struck; and in fact most of the distance, 

 especially its upper part, these exposed ledges appear to have been much abraded 

 and by a force directed down the valley. I found, also, in at least three places, 

 such accumulations of boulders, as could not be accounted for in any other way 

 but by supposing them the moraines of glaciers. These are shown upon the map, 

 Plate VIII. The first one, after leaving Chester Factories and going eastward, 

 occurs a mile distant, on the south side of the river, lodged at the foot of a pro- 

 jecting hill, as indeed I have always found them. It would seem, that as the 

 glacier passed such projections, which would form gorges, or at least obstructions 

 on one side, the fragments borne along by it would be shaken off. 



The second example is on the same side of the river, three and a half miles 

 below the Factories. The third is on the north side of the river, near' the house, 

 occupied when I visited the spot, by Ethel Osborne. This I think is the best 

 example. The large and for the most part angular fragments lie along the side of 

 a hill that rises 125 feet above them, and they rise above the river perhaps 100 or 

 200 feet. The great size, angular form, and large amount of these fragments, 

 struck me as rendering their glacier origin extremely probable, taken in connection 

 with the rounded aspect of the projecting bluffs. The descent from the Factories 

 to Chester village, however, by my aneroid barometer, is only 246 feet, or 41 feet 

 in a mile, which gives a slope of only 0° 27'. This is more than double some of 

 the slopes of ancient glacier action in the Alps. {Be la Bec/ie's Geological Observer, 

 p. 269. Philadelphia, 1851.) It ought to be stated, that in several places along 

 this valley, I found river action 150 feet above the present stream, so that the 

 original slope may have been much modified. Besides, immediately west of 

 Chester Factories, the mountains, whence the glacier must have come, rise much 

 more rapidly, and the grade of the crooked valley, along which the Western rail- 

 road is carried, is sometimes as high as 90 feet to the mile. This upper part of 

 the valley I have not examined carefully with reference to glacier action. But if 

 a thick -glacier came down from the high region west of the Factories, we can 

 easily conceive its lower extremity to be pushed forward four miles upon a more 

 moderate slope. For Becket, which lies at the summit of this elevated region, is 

 more than 1200 feet above the Factories, and only five or six miles distant. 



These were the first accumulations of detritus that I had met in our country that 

 bore any satisfactory resemblance to the moraines of Alpine glaciers. Those that 

 had been pointed out to me were composed of materials that had been extensively 

 modified by water. And I ought to add, that those which I now refer to glaciers 

 on Westfielcl and Deerfield rivers, have undergone some changes from the action 

 of water, subsequent to that of glaciers. In some cases it is obvious that water 

 has stood entirely or partially above the moraine and covered its surface at least, 

 with rounded and sorted materials; so that terraces may frequently be seen par- 

 tially resting upon the moraines. The same thing may be seen in the Alps. In 



