1858.] DAWSON LOWEK COAL-MEASUBES. 65 



and gypsums, with the exception of a limited space near the Ken- 

 net-cook and Five-mile Eivers, occupied by beds which, perhaps, 

 represent the middle coal-measures. These two lines of appearance 

 run in a north-eastern and south-western direction, and are distant 

 ten or fifteen miles from each other. The waters of Cobequid Bay 

 and Minas Basin, perhaps, fill another synclinal trough, which, 

 however, in the upper and narrower end of the bay appears merely 

 as a depression along an anticlinal axis ; and we do not observe the 

 lower coal-measures again until they are thrown up, in a very dis- 

 turbed condition, along the south side of the Cobequid Mountains, 

 where we have another line of outcrop, running east and west. 

 Here they appear as a continuous belt, eighty miles in length ; but 

 it is not easy to establish any boundary between them and the true 

 coal-measures, which are also present*. 



This appears to arise from the slender development of the marine 

 parts of the system near the mountains, and the disturbed condition 

 of the whole. These hills, indeed, appear to have retained their 

 position during the whole coal-period ; and semiterrestrial condi- 

 tions prevailed along their south side during the time when the 

 marine limestones were being formed at a greater distance from their 

 base. Hence in some localities, as at Folly River, we have the 

 coal-measures approaching the base of the hills, and underlaid by 

 conglomerates without any marine limestones, while, at a greater 

 distance from the hills, the marine limestones arise from beneath 

 these same coal-measures. In other places, as at the IS^orth River, 

 the limestones appear under the coal-measures, or at least the 

 greater part of them ; and, again, at Salmon River a limestone with 

 encrinal remains appears to be inserted in the midst of true coal- 

 measures. 



This original irregularity of deposition is now compKcated by a 

 multitude of fractures. The best section that I have had an 

 opportunity of examining, in this district, is that of FoUy River, 

 which appears to show, at the base of the Carboniferous system, in 

 descending order — 



Estimated thickness. 

 1st. Reddish and grey sandstones with a bed of 



conglomerate 300 feet. 



2nd. Dark shales and grey sandstones, with thin 

 coaly layers, containing Poacites and Stig- 

 maria, and probably representing the lower 



coal-measures 200 ,, 



3rd. Coarse conglomerate, containing fragments 

 of the metamorphic rocks of the hiUy range 

 on which it rests 450 „ 



There seems no reason to doubt that the shales in this section 

 correspond with the Horton Bluff series, and the conglomerate with 

 the sandstones which underlie that series. 



Along the northern side of the Cobequid Range, and its eastern 



* Quart. Journ. Greol. Soc. vol. iv. p. 52. 

 VOL. XV. PART T. F 



