8 ROYAL SOCIETY OF CANADA 



the Annapolis Valley was presented. Xo attempt was here made to in- 

 dicate a nomenclature for the horizons of the different formations of the 

 province, other than the use of the term Primitive for certain granite 

 masses, which are a portion of the great central area, and the term Tran- 

 sition, applied to some of the altered slates, which are in contact with 

 these at dilTorent places. The terms trap, sandstone, and slate, are 

 employed, and the paper is of considerable value as relating to the dis- 

 triliution and mode of occurrence of some of the leading economic 

 minerals. 



In the meantime Gesner, possessed with an ardent love of geologi- 

 cal pursuit^, and having a mind well fitted to correlate the various phe- 

 nomena found in the rocks of the Atlantic provinces, had been quietly 

 pursuing his studies of the complicated problems there presented. The 

 result? of his first observations appeared in a treatise on. the Mineralogy 

 and Geology of Nova Scotia in 1836, already alluded to. In this volume 

 the nomenclature was arranged under somewhat different heads from 

 those given by Bigsby for the rocks of the west. He classified the vari- 

 ous groups into districts, which were practicilly named from the general 

 character of the rocks peculiar to each. Thus from the predominance 

 of granites along the Atlantic coast of the province, he placed his lowest 

 division, which he styled the Primary district, as a belt extending from 

 the southwest extremity, along the whole eastern side of the peninsula 

 of Nova Scotia to the island of Cape Breton. A second belt, in which 

 the predominating rocks were clay slates, he outlined for its whole 

 length, through the centre of tlie province, regarding them as newer 

 than the rocks of the Primary division. This area he styled the Slate 

 district. It was followed northwesterly by the great series of reddish 

 shales, slates and sandstones, which now include formations from tlie 

 Silurian to the Trias, both inclusive, and this following out his 

 scheme, he termed the Red Sandstone district. In this also was 

 included what is now known as the Coal formation; while to the great 

 ridge of volcanic rocks such as basalts, diabase and amygdaloids, he 

 assigned the name Trap district. This system of nomenclature, it will 

 be observed, was based upon the physical and lithological characters, 

 and largely upon the predominant rock masses in each. 



In this volume of Gesner's a small map of the province appeared, 

 showing the delimitation of the several divisions as then imderstood. 



In 1843, Sir Charles Lyell made a tour of the northern portion of 

 the province of Nova Scotia, with the object of studying the geological 

 structure of the rocks in that district. In company with Gesner and J. 

 \V. Dawson he examined in some detail the rocks which had been 

 grouped by Gesner in the Red Sandstone division ; and as a result these 



