Address before the Association of American Geologists. 255 
ice melted away.* ‘The lateral moraines are perhaps most com- 
mon, especially if, with Dr. Buckland, we regard our terraced val- 
leys as modifications of these; but I am confident that in our 
mountain valleys, the teignuieval and the medial moraine are not 
infrequent. Ihave long been convinced that the agency of ice 
was essential to explain these accumulations ; but I was not aware 
that their antitypes existed in the moraines of the Alps. 
"In the second place, this theory explains in a most satisfactory 
manner, the smoothing, polishing and furrowing of the rocks at 
different altitudes, All these effects are perfectly produced be- 
neath the glaciers in the Alps; nor can I conceive of any other 
agent by which the work could be executed. It certainly was 
not done by currents of water alone. One has only to cast his 
eye upon the splendid plates by Agassiz, of the polish and strie 
produced by the glaciers, to be satisfied that the multitudes of 
sane of pe Sox IO New England, and in New 
In the third er it explains the ransforttion of bowen 
and their lodgment upon the cre 
tains, and that often without having ee neles roun ‘ 
In the fourth place, it accounts for plier iit wie 
of clay and sand above the drift. For it furnishes the requisite’ 
quantity of water to fill the — and the means se —— 
up their outlets for a season. — 
In the fifth place, it shows us- ne sions deposits of clay and 
Sand are almost completely destitute of organic remains, either of 
animals or plants, although signee aroncere must: have ~—_ 
Consumed in their formation. — 
“In the sixth place, it accounts Sertintns wind il sieiiiieghel 
nomena connected with diluvial action, which seem to me inex- 
Plicable on any other known principle. I shall name only two. 
The first is, that the northern slopes of some of the mountains 
of New England, although quite steep, and» their summits 
vexhibit _— and furrows which commence several 
ip 
cript of sme sb eset ageriy will be ‘foals hopetsne on 
the Geology. of ‘me tts, publis . but more numerous descriptions 
vings are given in: ti a Repro just published. See especially Figs. 
and 74, of the ‘wood cuts, a 2 3 of the lithographs. — | 
