§0 THE CANADIAN NATURALIST. [Vol. vi. 



magnetic iron. The non-magnetic portion was soluble in acids 

 and fused bisulphate of potash, with the exception of 4.8 per 

 cent, of silicious residue, and the solutions contained, besides iron, 

 a considerable proportion of chromium, and 23.15 per cent, of 

 titanic acid, derived from the titanic iron ore, which made up a 

 large portion of the sand. (Geology of Canada, page 520.) 



The proportion of these ores to the whole mass of ordinary 

 silicious sands is, generally, by no means large, but the action of 

 moving water effects a concentration of the mixture, separating 

 the lighter silicious grains more or less completely from the 

 heavier portions, which consist chiefly of the iron ores, generally 

 with a small quantity of grains of garnet. This separation is 

 effected, on a large scale, by the action of the sea, under the in- 

 fluence of the winds and tides, and the result of this action occa- 

 sionally gives rise to remarkable accumulations of these heavy 

 iron sands, along the present sea- beaches. A similar process in 

 past ages, during the deposition of the stratified sands, which are 

 now found at heights above the sea-level, has sometimes arranged 

 the iron grains in layers, which are seen to alternate with the 

 lighter silicious sands, as in the deposits of to-day. 



Accumulations of these iron sands are met with in many coun- 

 tries. They are found on the shores of Great Britain, along the 

 borders of the Baltic and Mediterranean, and abundantly on the 

 coast of New Zealand. In some parts of Hindostan and Mada- 

 gascar the grains of iron ore are extracted by washing from the 

 sands of the country, and employed by the natives in their primi- 

 tive furnaces, for the manufacture of iron on a small scale. The 

 iron sands of New Zealand have of late attracted particular at- 

 tention from their great extent and richness. According to 

 Hochstetter, the shore of the northern island from Kaipara to 

 Taranaki, a distance of 180 miles, is bordered with a thick layer 

 of iron sand, which contains, according to different analyses, from 

 six to eleven per cent, of titanic acid. 



In North America, black iron sands abound in many places. 

 They occur in great quantities in the lower St. Lawrence, as will 

 be hereafter described, and are met with, in smaller amounts, at 

 various points to the south-westward, along the valley of the St. 

 Lawrence and the great lakes. Thus, a deposit of black sand at 

 the outlet of Like Huron, near Sarnia, attracted some attention, 

 a few years ago; while along the north shore of Lake Erie this 

 sand is, in some places, found in such quantity that attempts were, 



