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ceeded by stratified fossiliferous elay slate, greywacke, and grey- 

 wacke slate. Fossils of a Silurian character occur in the latter. The 

 lowermost of these deposits, where they have ceased to afford organic 

 remains, may be regarded as Cambrian. A complete zone of Silurian 

 beds encircles and immediately covers the Cobequial granitic range, 

 'i'he non-fossiliferous slates and the Silurian beds of the province 

 agree in the circumstance, that their strata dip away from the ad- 

 jacent ridges of granitic rock at angles of high elevation. 



4. Old red sandstone, or Devonian group. — Above the Silurian beds 

 there occurs, in several parts of the province, a bright red micaceous 

 sandstone or conglomerate, accompanied by thin beds of red shale 

 and marly clay, and in some places containing seams of fibrous gyp- 

 sum. Hitherto no organic remains have been found in it. At Advo- 

 cate Harbour and on the Moose River this sandstone is seen lying 

 unconformably beneath the coal-measures. At the latter locality the 

 sandstone dips W. 21°, and the coal-measures dip N.N.E. 60°. It 

 !s from a joint consideration of the mineral character of this forma- 

 tion, and its relative position as compared with the coal-measures, 

 that the author has regarded it as the equivalent of the old red sand- 

 stone. 



5. Coal-measures. — Unless the calcareous deposits of the districts 

 of Pictou and Stewiack should be found to belong to the carbonife- 

 rous limestone of New Brunswick and of Great Britain, the author 

 is not aware that there are any beds in the province which are refer- 

 rible to that formation. The coal-field which skirts nearly the- whole 

 of the northern coast of Nova Scotia, and which occupies the gi-eater 

 part of the isthmus, is a small part of that extensive coal-field of 

 which the remainder is situated in the province of New Brunswick. 

 In Nova Scotia, the commencement of the coal-field towards the east 

 is near Pomket Harbour, between the 45 th and 46th parallels of north 

 latitude and the 61st and 62nd meridians of west longitude. Hence 

 it extends along the whole northern coast of the province of Nova 

 Scotia to Bay Verte, where it enters the province of New Brunswick. 

 The area of the coal-field in Nova Scotia is about 2500 square miles, 

 and that of the coal-field in New Brunswick about 7500 square 

 miles, making the total area of the coal-field in the two provinces 

 10,000 square miles, and in this computation is not included the 

 coal-field of Cape Breton. The above coal-field may therefore be 

 considered as one of the most extensive on the face of the globe, and 

 as of great value to Great Britain and her North American colonies. 

 The strata occupying this extensive area consist 



1. Qf gray, red and chocolate- coloured sandstones and conglome- 

 rates ; 



2. Of red, blue and black shales ; 



3 . Of shelly limestones ; 



4. Of clay ironstone ; 



5. Of coal, of which the bituminous variety occurs throughout 

 the district. 



All the strata abound in the remains of the plants that are usually 

 found in the coal-measures. 



