196 STRATIGRAPHICAL GEOLOGY. 



nation seems possible ; and if this Iiypotliesis be adopted, tliere is no longer any need 

 of that which supposes the submergence of New England up to the base of the head of 

 Mt. Washington and no higher, leaving the head in the air to escape the general round- 

 ing and polishing action. It becomes easy to consider the external difference due 

 rather to the difference of the rock formations above and below that horizon. 



It is to be hoped that a systematic explanation will be made of this interesting region 

 and the structure made out and mapped, so that we may arrive at conclusions, instead 

 of venturing conjectures. 



Viezvs of T. Stcrry Hunt. At the Cambridge, Mass., meeting of the 

 American Association for the Advancement of Science, 1849, ^r. Hunt 

 made an oral communication upon the results of the geological explora- 

 tions of Canada, and the conclusions to be derived therefrom respecting 

 the age of the New England rocks. The substance of these remarks was 

 printed in t'he official record of the meeting, also in American Journal 

 of Science, II, vol. ix, p. 12. Reference is made to the section from Lake 

 Memphremagog across to Canaan, Vt., by W. E. Logan, in the report on 

 the geology of Canada for 1847-48, which afforded the data from which 

 the conclusions were drawn. The fossiliferous rocks of the St. Francis 

 valley are referred to the Niagara grouj^, which are continuous with the 

 "calcareo-micaceous formation of Prof. Adams," in Vermont. Resting 

 upon this Niagara group in Gaspe is a body of arenaceous rocks, 7000 

 feet thick, corresponding to the Chemung and Portage groups in New 

 York. "To this," he says, "may perhaps be referred in part the rocks of 

 the White Mountains." 



Similar views are met with in a paper on the Crystalline Limestones 

 of North America, in the American Journal of Science, II, vol. xviii, p. 

 199, 1854. 



When we consider the geographical position of the Upper Silurian rocks in the 

 Connecticut Valley on the one hand, and the coal field of south-eastern Massachusetts 

 on the other, we can scarcely doubt that the intermediate gneissoid and hornblendic 

 rocks, with their accompanying limestones, are the Devonian strata in an altered 

 condition. 



In 1870 Dr. Hunt wrote a letter to Prof. Dana upon the geology of 

 eastern New England, in which he proposed the name of Terranovan 

 series for the rocks to which the White Mountains were supposed to 

 belong; and conjectured that their age was "between the Laurentian 



