Topographical Features of the JSfeio Hnven region, 49 



valley if brought by icebergs, should hence have come from the White 

 ^lountains, or perhaps from some Green Mountain peak, for these would 

 have been the only summits above the v^^ater in a sea covering the 

 valley to a depth of four thousand or more feet (the depth that the 

 <listribution of boulders requires). But, on the contrary, the boulders 

 of the New Haven region, 1000 tons and smaller in size, are mainly 

 from the trap and sandstone hills of the valley itself, either in Con- 

 necticut or Massachusetts, and the adjoining plateau of gneiss, etc. ; 

 they are from the depths of the imagined sea, and not from the 

 heights above it. Icebergs could not therefore have done the work of 

 transportation. In the Glacial era, then, all New England and, prob- 

 ably, the whole northern portion of the continent, was covered with 

 ice. It is well known that the Glacier theory is sustained by the ex- 

 plorers of the Alps, Professors Agassiz and Guyot.* 



4. Condition and Effects during the Glacial era. 



The Connecticut valley glacier lay under the general glacier-blanket 

 of the continent, or rather was a part of the lower portion of it. It 

 extended from the summits of the Green Mountains on the west to the 

 dividing height of land on the east, having a width of 100 to 120 miles ; 

 it was therefore sufficiently large to have almost entirely an independ- 

 ent motion, determined by the slope of the valley ; which would make 

 the prevailing direction of movement southward, or mostly between 

 south and 12° west of south. 



The direction, according to Prof. Hitchcock, of the scratches on 

 Mt. Monadnoc in New Hampshii'e, which extend even over its sum- 

 mit 3,718 feet in altitude, is southward; and the same authority 

 gives this as the course in Deei-field, Greenfield and other places in 

 the Connecticut valley, as well as on Mt. Tom and Mt. Holyoke. It 

 is the course also in one of the gorges of Mt. Carmel. East of the 

 Hanging Hills of Meriden it is south-southwest, and Percival at- 

 tributes the unusual amount of westing to the trend of the adjoining 



* Dr. Newberry, in an excellent paper on the Surface Geology of the Great Lakes 

 and the Valley of the Mississippi (Ann. Lye. N. York, ix, 1869), sustains the glacier 

 theory of the drift for the country, but gives reasons for making part of the area of 

 the Great Lakes an iceberg region in the closing Glacial era. The author presents 

 many other points of interest with regard to the successive events of the Glacial and 

 Champlain eras, and in the course of his remarks, observes that there could have been 

 no true lateral moraines. He makes the depositions of drift over the hills and the 

 stratified material of the valleys and plains essentially cotemporaneous, regarding them 

 as having resulted partly from iceberg transportation, and partly from distribution by 

 waters flowing away from the margin of the ice, or from beneath it, as it slowly melted. 



Trans. Connecticut Acad., Vol. II. 5 Sept., ]869. 



