10 



One of the most marked peculiarities in the geology 

 of Vermont, is found in the general dip of the stratified 

 rocks, which is, with a few trifling exceptions, towards 

 a synclinal axis extending north and south near the 

 centre of the Green Mountain range. Along the shore 

 of Lake Champlain the rocks are nearly horizontal, 

 having only a slight easterly dip ; but the dip increases 

 pretty uniformly, in proceeding eastward, till it becomes 

 vertical at a line a little westward of the principal 

 summits of the Green Mountains. From this line, for 

 a distance of seven or eight miles eastward, the dip of 

 the strata continues nearly vertical. This space 

 embraces the highest part of the mountain range, and, 

 to the eastward of it, the general dip of the rocks is 

 distinctly westward ; but the rocks are here more dis- 

 turbed, and the dip less uniform, than on the west side 

 of the mountains. 



With regard to the question, whether the rocks, 

 which form the Green Mountains and extend east- 

 ward to Connecticut river, are truly primary, or ante- 

 palffiozoic, as was formerly supposed, or are metamor- 

 phic silurian rocks, which are newer than the Cham- 

 plain group, as has been more recently suspected, I 

 would only observe, that evidence in favor of the latter 



originally formed in the bottoms of ponds ; but these ponds have, 

 in many cases, entirely disappeared, and the places they occupied 

 became dry land. One of the most interesting of these marl-beds 

 is in Williamstown. It covers about seven acres, and is in some 

 parts 18 feet deep. It is a very pure carbonate of lime, consisting 

 entirely of comminuted fresh water shells. This marl is formed 

 into a paste, moulded in the form of bricks, and then burned in a 

 kiln. The quicklime thus obtained is quite white, and for most 

 purposes is scarcely inferior to that obtained from the Champlain 

 and Taconic limestone. 



