96 L. "W. BAILEY ON GEOLOGICAL CONTACTS AND ANCIENT 



upon the Devouiau strata, and thus originating a misconception which for some years 

 obscured the true structure of the region. No contacts of Devonian and Silurian are to be 

 found in this part of the Province ; and though such contact has been supposed to occur in 

 connection with the argillites bordering the central coal-field, the age and relations of 

 these rocks can hardly be regai'ded as definitely settled. 



In rising to the Lower Carboniferous, we reach an horizon and a series of contacts 

 which, whether they be regarded simply in themselves, or in their accompaniments of 

 erosion and lithological contrasts, constitute the most marked boundary line in the physical 

 history of New Brunswick. Resting indifferently and unconformably upon all the older 

 formations (Laurentian, Huronian, Cambrian, Upper Silurian, Devonian and granite) ; com- 

 posed of material, in some instances fossiliferous, derived from all these formations, and 

 varying in its aspect with the nature of the rock on which it rests ; exhibiting no sign of 

 those metamorphic influences which have hardened, crystallized, or debitumenized all the 

 older beds beneath, even to the Devonian, but, on the contrary, being even in its lowest 

 portions saturated with petroleum and containing deposits of Albertite, — the study of this 

 formation, fromi whatever point of view, suggests conclusions of the greatest interest. So 

 marked and so wide-spread are the contrasts referred to, not in New Brunswick only but 

 everywhere around and over the Acadian basin, and so important were the movements by 

 which these contrasts were determined, that we may well style the epoch in which they 

 occurred the Acadian or Devonian revolution. It was, indeed, probably at this time that 

 the Acadian basin proper first became clearly outlined by the elevation of its bordering 

 hills, and when all the more marked of those physical features which now distinguish it 

 became determined. It is remarkable that both the breadth of the formation and its 

 elevation above the sea-level progressively increase in passing from the western to the 

 eastern side of the Province, beds of this age in the former being rarely met with more 

 than two or three hixndred feet above the sea, and mostly confined to the valleys, while in 

 the opposite direction they gradually mount the sides of the hills, and, in the case of 

 Shepody Mountain, in Albert, cap the latter at a height of twelve hundred feet. There 

 is, however, good reason to believe that they formerly spread over much wider areas and 

 possessed a considerably greater thickness than they now exhibit. Thus, not only on 

 Shepody Mountain, but on other portions of the southern hills, at scarcely inferior eleva- 

 tions, strata of this age may be observed in positions which are not far from horizontal, 

 and which appear to be merely the detached and isolated fragments of a formation, 

 which at one time must have been continuous, and which deeply buried the entire 

 region in which they are found. So again, similar rocks, showing similar evidences of 

 marine origin, are found in scattered areas over portions of York, Carleton and Victoria 

 Counties, which are also but little inclined, and which have probably been disconnected 

 by erosion. Some of these in the Beccaquimic region cannot well be less than 800 or 900 

 feet above the sea-level. In King's County the peciiliar topography of such localities as 

 the Dutch valley and Upham, are evidently due to the removal of extensive masses of this 

 formation by denuding processes. 



Still further evidence of the extent to which this formation has suffered by removal is 

 shown in its relations to the overlying coal-measures, and brings us to consider another 

 line of contact, of special interest as bearing upon the important question of the coal- 

 producing capacity of this formation. There can be no question that, at many points, the 



