56 THE CAMBRIAN. [bull. 81. 



NOVA SCOTIA. 



Tbe altered or metamorphic slate belt of the Atlantic coast of Nova 

 Scotia is represented on an early geological map by Dr. Aoraham Ges- 

 ner 1 as extending from Cape Canso to Cape Sable. He states that the 

 area is within the primary district and composed principally of granite, 

 gneiss, and mica slate. A general description of the rocks is given in 

 the account of the local geology of the townships in which they occur. 



At a meeting of the Geological Society of Loudon on May 10, 1843, 

 Dr. Gesner 2 presented to the society a geological map of Nova Scotia, 

 accompanied by a memoir on the geology. In the text 3 the lowermost 

 of the Silurian rocks devoid of animal remains is referred to the Cam- 

 brian. The map was not published with his paper. It appeared in 

 1845 4 in connection with papers by Mr. Eichard Brown, on the geology 

 of Cape Breton, and Mr. J. W. Dawson, on the Lower Carboniferous 

 rocks or gypsiferous formation of Nova Scotia. The strata now pro- 

 visionally included in the Cambrian group are indicated on the map 

 as micaceous and chloritic slates, clay slate, quartz rock, and gray wacke 

 slate. They extend entirely around the central area of granite and 

 syenite, and are separated from the Atlantic coast by a broad belt of 

 color designated as granite. At a later date Gesner described the strat- 

 ified non -fossil iferous rocks or Cambrian group of Nova Scotia 5 as an 

 extended belt of hornblende slate, chlorite slate, clay slate, gray wacke 

 slate, and quartzite, succeeding the granite and its associates, and with 

 th"em occupying almost the whole of the Atlantic side of the province. 

 No fossil remains have been found in any of these metamorphic masses. 



In 1850 Dr. J. W. Dawson described the Atlantic coast series as fol- 

 lows: 



The prevailing stratified rocks in this group are compact and flaggy gray quartz- 

 ite (often weathering white), mica slate, and clay slate, the latter usually of dark 

 colors, and occasionally passing into flinty slate and quartzite. * * * 



The hypogene rocks associated with them are white and flesh-colored granite, 

 which has penetrated the metamorphic rocks in large irregular bauds and masses. 6 



As a result of his study of this group of rocks Dr. Dawson concluded 

 that they belonged either to some of the older members of the Silurian 

 system or to a still earlier period. In the first edition of the Acadian 

 Geology Dr. Dawson stated that the rocks are certainly older than the 

 Devonian ; and he was inclined to believe that they represented the 

 Potsdam sandstone aud Utica and Hudson Eiver shales, in an altered 

 condition. 7 On the accompanying map their geographic distribution 



1 Remarks on the geology and mineralogy of Nova Scotia. Halifax, N. S., 1836, pp. 272. 



2 A geological map of Nova Scotia, with an accompanying memoir. Geol. Soc. London, Proc, vol. 

 4, 1843, pp. 186-190. 



3 Op.cit.,p. 187. 



4 Geological Map of Nova Scotia. (Accompanying papers hy J. W.Dawson and Richard Brown,) 

 Quart. Jour. Geol. Soc, London, vol. 1, 1845, oppo., p. 23. 



6 The industrial resources of Nova Scotia. Halifax, N. S., 1849, pp. 233, 234. 



6 On the metamorphic and metalliferous rocks of eastern Nova Scotia. Quart. Jour. Geol. Soc, Lon- 

 don, vol. 6, 1850, p. 348. 



Acadian Geology, 1st Edition, Edinburgh, 1855, p. 367. 



