166 Dr. How on the Mineralogy of Nova Scotia. 



of these I described the ores of manganese and their uses ; and I 

 select for the first subject in the present series of papers these 

 ores, more particularly with reference to their chemical composi- 

 tion and mineralogical characters. 



Manganite. — This species occurs abundantly at Cheverie, on 

 the south shore of the Basin of Minas, in Hants Co., where it is 

 found in nodules, sometimes of considerable size, on the beach, 

 about twenty rods above high-water mark, and on the upland 

 nearly two miles from the water. It is also met with at Walton, 

 some miles to the east of Cheverie on the Petite River, where I 

 have picked it up in the fields, and where a bed of it is said to 

 crop out in a low hill on the river-side. It is mostly of compact 

 crystalline structure, of a dark-grey colour, gives a brown streak 

 and powder, and has hardness a little above 5. In the compact 

 pieces small cavities are sometimes found, lined with black lus- 

 trous prismatic crystals affording a brown streak; these most 

 probably consist of the essential elements of the species. The 

 mineral is associated with barytes and calcite, and sometimes 

 with pyrolusite. The geological formation of the surrounding 

 district is lower carboniferous ; the prevailing rocks are gypsum 

 and limestone, sometimes containing magnesia, the latter being 

 that in which I believe the ores of manganese always occur in 

 this part of Nova Scotia. 



A specimen from Cheverie was analyzed : the water and 

 oxygen were determined by ignition in connexion with a tube 

 filled with chloride of calcium ; the amount of binoxide of man- 

 ganese was ascertained by the oxalic-acid process, and the corre- 

 sponding quantity of sesquioxide calculated ; the siliceous gangue 

 containing a small amount of barytes was estimated by action 

 with hydrochloric acid as a solvent for the soluble constituents, 

 among which were a little iron and baryta, which were not 

 weighed. The results were these : — 



Water 1O00 



Sesquioxide of manganese* . 86*81 



Gangue 1'14 



Oxide of iron, baryta, and loss. 2*05 



100-00 



The amount of oxygen lost on ignition was 3*57 per cent., and 

 the theoretical loss, in the change of the Mn 2 3 found into 

 Mn 3 O 4 , is 3*01. These numbers leave no doubt that the mineral 

 is the hydrated sesquioxide of manganese or manganite, the theo- 

 retical composition of which is — 



* Binoxide found =i 4/73. 



