OF CENTRAL CANADA PART V. 353 



crystals of greenish-white feldspar ; or otherwise they present the 

 form of a more or less compact or granular greenstone, properly so- 

 called. Grey doleritic dykes occur around Gaspe* Bay, as at Tar 

 Point (referred to on a preceding page) and elsewhere ; and green 

 feldspatho-porphyritic dykes are exceedingly numerous on the south 

 coast at New Carlisle, as described many years ago by the late Sir 

 William Logan (Geological Reports : 1844, 1863). Trappean hills 

 and dykes occur also at other points along or near the coast between 

 the Cascapedia and the Restigouche at the head of the Bay of 

 Chaleurs. 



Glacial and other surface deposits : These are spread very generally 

 within this district, as elsewhere, over the various rock-formations 

 of the country. They comprise, in ascending series : (1), Beds of 

 auriferous gravel and magnetic sand ; (2), Boulder-clays or Drift de- 

 posits, proper, consisting of accumulations of clay and gravel with 

 boulders of crystalline and other rocks ; (3), Beds of Leda Clay (a 

 more or less deep-sea formation) and Saxicava Sand (a shore-line or 

 shallow-sea deposit : page 342) ; and (4), sundry superficial deposits 

 of comparatively recent origin. The Drift clays in many parts of the 

 Eastern Townships and adjacent area, are underlaid by (and also 

 partially mixed with) layers of gravel and black magnetic sand, 

 containing, very generally, fine grains, and occasionally small nug. 

 gets of free gold. These auriferous deposits have been recognized in 

 the beds of most of the streams and rivers which flow through this 

 section of the Province, and especially in the St. Francis, Chaudiere, 

 Famine, Riviere des Plantes, Etchemin, Gilbert, Metgerniet, and 

 Riviere du Loup.* The slate rock which underlies most of the 

 Chaudiere country, although exposed in many places, is covered as a 

 rule, from the surface downwards, by a deposit of alluvial earth, clay, 

 boulder-clay, black magnetic sand, and coarse gravel, varying from a 

 few feet to over 1>0 feet in thickness. There is hardly a single 

 stream connected with the Chaudiere valley that does not carry 

 more or less gold, chiefly in the gravel which fills the cracks and 

 crevices of the rock which forms its bed. But the greater portion of 

 this surface gold has long since been extracted- at least, as regards 

 the smaller streams and rivers where the bed-rock can be easily got 



* Of Beauce County : not the Riviere du Loup of Kamouraska and Teraiscouta on the St. 

 Lawrence 



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