No. 1.] MATTHEW — GEOLOGY OF NEW BRUNSWICK. 95 



plain of eastern New Brunswick, and surmounted the more east- 

 erly ridges along the north shore of the Bay of Fundy, there 

 beino; meridinal sfrooves on these rid^-es to the hei";ht of 1000 

 feet. Hills of this altitude must have been surmounted by a 

 continental glacier such as we have supposed, else its motion 

 would have been arrested at their base. But as an extensive 

 plain stretches away to the north from the base of these hills and 

 passes beneath the Gulf of St. Lawrence, a slope like that of the 

 great Swiss glacier above mentioned, could not have carried the, 

 ice over the summit of this range, unless the mass of ice were 

 two and a-half miles thick on the depression now occupied by the 

 Bay Chaleur. 



It is evident, however, from several considerations that such a 

 mass of ice could not have existed in Acadia. A glacier of this 

 depth would have been double the height of Mount Washington, 

 the highest peak in Eastern North America, upon which there 

 are no stride at a greater heis-ht than 5000 feet. And the exist- 

 ing continental glacier of Greenland to which the supposed Aca- 

 dian glacier has been compared, averages only about 2000 feet in 

 thickness. The non-existence of a glacial mass exceeding this 

 thickness may also be inferred upon physical grounds — the inter- 

 nal heat of the globe alone, would prevent it from attaining great 

 thickness. From the comparison of observations carefully made 

 in different parts of Europe it was inferred some years since that 

 terrestrial heat increased in descending toward the centre of the 

 earth at the rate of one degree Fahr. for every sixty feet of de- 

 scent ; but it was suspected that the observed rate of increase in 

 temperature was materially effected in the case of mines (where 

 the observations were chiefly made) by heat evolved during the 

 decomposition of sulphurets of the metals, and in the case of 

 artesian well, by warm waters rising from great depths through 

 fissures in the earth's crust. A means of correcting these obser- 

 vations has been afforded by the Mount Cenis tunnel beneath 

 the Alps. This artificial passage connecting Italy and Savoy is 

 between seven and eight miles long and at one point more than a 

 mile beneath the crest of the Alps ; it therefore gives peculiar 

 facilities for testing the heat of the earth at a point twice as far 

 beneath the surface as any of those upon which the sixty feet 

 ratio was based. Moreover, the rock of Mount Frejus, under 

 which the tunnel runs, is singularly homogenous and almost en- 

 tirely devoid of sulphurets ; nor were any thermal springs detected, 



