80 



SCIENCE 



[N. S. Vol. XLIX. No. 1256 



One other elevation should be mentioned. 

 Mount Aseutney in Windsor is a conspicuous 

 object in the Connecticut Valley as it stands 

 alone twenty miles from any other hill. Of 

 this it must be sufficient to note that its struc- 

 ture is unique among Vermont mountains 

 and unusually complex, as any one who will 

 refer to Dr. E. A. Daly's account in Bulletin 

 209, U. S. G. S., will find. Dr. Daly says: 



Aseutney owes its existence to a great stock of 

 quartz syenite. 



Also 



Mount Aseutney is, like most New England 

 mountains, a residual or erosion, a monadnock over- 

 looking a dissected rolling plateau. 



In so mountainous a region as that of Ver- 

 mont the elevations of all sorts must form 

 the most obvious part of its physiography, 

 but in any other than an arid region where 

 there are mountains there must also be streams 

 and lakes. Everywhere in Vermont the stern, 

 rugged, impressive miountain scenery is soft- 

 ened by. the charm of stream and lake. Aside 

 from Champlain and Memphremagog, there 

 are not far from four hundred lakes and 

 ponds in the state. Some are but a fraction 

 of a mile long, others several miles. Most of 

 them are of glacial origin. The streams axe 

 innumerable. There are four rivers that 

 empty into Lake Champlain, although they 

 rise in the eastern part of the state and thus 

 do not conform to the general trend of surface 

 features. These, the Missisquoi, Lamoille, 

 Winooski and Otter have found their way 

 across the mountains. They are antecedent 

 streams and therefore old. Other rivers flow 

 into the Connecticut and a few others else- 

 where. Nearly all have formed deltas. 



[Necessarily the general character of Ver- 

 mont physiography is much modified by the 

 character of the rocks. As one crosses the 

 state from east to west he will find at least 

 a dozen belts or strips of differing rock ma- 

 terial. Along the Connecticut River are 

 schist and slate for the most part, while be- 

 tween these and the mountains are schist, 

 limestone, conglomerate quartzite, etc. The 

 common schists are sericite and phyllite. 



The age of these beds, some of which ex- 

 tend through the length of the state, some 

 only for a few miles, has been long in doubt, 

 but within the last few years Dr. C. H. Rich- 

 ardson, working on the Vermont Survey, has 

 studied the rocks of eastern Vermont and has 

 been fortunate in discovering in limestone 

 beds at many localities crushed graptolites, 

 some of which have been identified by Dr. 

 Ruedeman as undoubtedly Ordovician. 



So numerous and widely distributed are 

 these outcrops that it appears quite certain 

 that eastern Vermont is largely Ordovician, 

 though there may be a small amount of 

 Cambrian. As has been indicated, much of 

 the rock east of the Green Mountains is highly 

 metamorphosed and when the mountains 

 themselves are reached exceedingly complex 

 structure is found. It will probably be a long 

 time before all the intricacies of Green Moun- 

 tain geology are disentangled. 



For a few miles west of the mountains the 

 rocks are similar to those found in the Con- 

 necticut Valley east of them. Farther west 

 there are sedimentary rocks which have been 

 somewhat changed, and near the lake others 

 which are unchanged. The shores of Lake 

 Champlain afford many excellent opportuni- 

 ties for studying the Lower Cambrian, and the 

 divisions of the Ordovician from Beekman- 

 town limestone to Utica shale. All headlands 

 on the eastern shore of the lake are of these 

 beds, as are nearly all the islands in Lake 

 Champlain. 



The last period in the making of Vermont 

 physiography is, naturally, the Pleistocene. 

 The usual events of this age are too well known 

 to need repetition here and what the Pleisto- 

 cene was elsewhere it was in Vermont. There 

 is here no evidence that more than one ad- 

 vance of the ice came over the region we are 

 considering. Evidences of the action of the 

 glacier that moved over Vermont are every- 

 where and if other glaciers preceded it, all 

 traces of their coming have been removed by 

 the last. This seems to be of the time of the 

 late Wisconsin and it covered the highest 

 mountains, as scratches on bits of quartz en- 

 closed in the gneiss show. The gneiss itself is 



