18(50.] GEOLOGY AND MINERALOGY. 467 



the 27th of December, 1869, was postponed to January 31st, 

 1870. J. P. w. 



GEOLOGY AND MINERALOGY. 



.The Magnetic Iron Sands op Canada, by Dr. T. 

 Sterry Hunt, F.R.S. — Extract of a letter published in the 

 American Engineering and 3Hmng Journal of February 8, 1870. — 

 The sands from the mines of the crystalline rocks in Canada, 

 as in most other regions, hold considerable quantities of iron ore, 

 which along the shores of lakes and of the sea is seen partially 

 separated by a natural process of concentration through the action 

 of the water. The ancient marine sands which are found in the 

 lower St. Lawrence, from the present sea-level to altitudes of 

 seyeral hundred feet, are often banded and barred with layers dis- 

 colored by black iron ore grains, and in some places beds of several 

 inches in thickness are almost free from the admixture of silicious 

 sand. More generally, however, to obtain it of such a degree of 

 purity requires a process of artificial concentration by washing or 

 otherwise. The black sand thus obtained is not homogeneous, but 

 may be separated inio a magnetic and a non-magnetic portion, the 

 latter predominating in the washed sand. While the magnetic 

 part is nearly pure magnetic iron ore, the other portion contains 

 from thirty to thirty-five per cent, of titanic acid, and consists in 

 great part of titanic iron (menaccanite) with some admixture of 

 garnet. 



Successful attempts have been made to work these iron sands at 

 Moisie, where they are treated in bloomery fires, and are reduced 

 without difficulty, the daily yield of iron to each furnace being as 

 great as in the similar furnaces of Northern New York, where 

 noa-titaniferous ores are used. The bar iron thus produced is of 

 excellent quulity and retains no titanium in its composition, 

 while the fluid and readily crystallizable slags hold a great deal of 

 tit;inic acid as a silico-titanate. The layers of iron sand at the 

 Moisie are very rich, and the same is true of many other deposits 

 in that vicinity and at Mingan, Natashquan, and elsewhere ; but 

 in many localities there are great quantities to be obtained which 

 yield by washing from eight or ten per cent, to thirty or fifty per 

 cent, of heavy black sand. Attempts have been recently made to 

 purify these by means of a magnetic separator, which leaves 



