no. 1.] dawson — geology of nova scotia. 9 



2. Pre-carboniferous Rocks of Eastern Nova Scotia. 



The second paper, cabove referred to, is of a character so auto- 

 biographical, contains so little that is new in a scientific point 

 of view, and deals so unceremoniously with the reputations of 

 nearly all who have worked in the geology of Nova Scotia, that 

 it is difficult to criticise it without being personal. I shall en- 

 deavour however, to avoid this, and to confine myself to the 

 geological questions involved. 



The first attempt, after Dr. Gesuer's Geology of 1836, to deal 

 with the complexities of the older rocks in Eastern Nova Scotia, 

 was made nearly thirty years ago, in a paper on the Metamorphic 

 and Metalliferous Rocks of Nova Scotia, published in the Journal 

 of the Geological Society in 1850; a very imperfect attempt, no 

 doubt, but still a step of progress, and one involving much hard 

 labour under very difficult circumstances. Before preparing the 

 paper, I had examined lines of section from Pictou to the Atlantic 

 coast, and had collected fossils at Arisaig and on the East River 

 of Pictou. In this paper, the " shales, slates and thin-bedded 

 limestones of Arisaig" were referred to the Silurian system, on the 

 evidence of their fossils, as were also the similar rocks occurring 

 on the east side of the East River of Pictou. I was obliged, 

 however, to add that specimens taken to England by Sir C. Lyell, 

 with whom I had visited the East River in 1842, had been re- 

 ferred by palaeontologists there to the Lower or Middle Devonian 

 age, and that Prof. Hall, the best American authority on these 

 fossils, appeared to lean to a similar conclusion. 



The cause of this doubtful position of the matter is easily ex- 

 plained, without attaching any blame to the eminent geologists 

 above named. At that time the line of separation of the Devo- 

 nian and Upper Silurian was not very clearly defined ; and indeed 

 it may be said yet to be in some uncertainty, since it is only 

 within a few years that it has beea proposed to transfer the 

 Oriskany sandstone to the Upper Silurian,^ and in the latest 

 classification of the Gaspe series by the Geological Survey of the 

 Dominion,* no less than 880 feet of shales and limestones are 

 designated as "passage beds" between the two. In addition to 

 this, the fossils from the Nova Scotia beds were to a large extent 

 dififereot from those both of the New York series and of England, 



* Billing'tj Palaeozoic Fossils, 1874. 



