Dr. How on the Mineralogy of Nova Scotia. 169 



feet from the surface, taken as a sample of dressed ore, and 

 weighing about a quarter of a pound, gave me in the air-dry 

 state, in summer, 93*83 per cent, binoxide of manganese, with 

 barytes and a mere trace of iron. It is a very valuable property 

 of this ore, las regards its use by glass-makers, that when cleaned 

 it contains remarkably little iron. The first shipment sent to 

 England, consisting of about seven tons and a half, gave, on 

 analysis in Liverpool, 91 "5 per cent, binoxide, and less than a 

 half per cent, of iron. 



South of Teny Cape, at a distance of some ten miles, large 

 nodules of manganese ore are found resembling in appearance 

 those described as occurring in the "soil" at the former place. 

 One of these weighed 180 pounds ; a fragment from another, 

 weighing thirty-five pounds, was examined by Mr. H. Poole, a 

 pupil of mine. The mass was black, of unequal hardness, por- 

 tions scratching apatite, and therefore about 5 '5, while the rest 

 yielded easily to the knife. The powder of the harder parts was 

 nearly as black as that of the softer. The water of composition 

 was found by weighing in chloride of calcium ; the binoxide of 

 manganese by oxalic acid; the results were these: — 



Hygrometric water . 



. . 1-660 



Water of composition . 



. . 3630 



Peroxide of iron . 



. . -603 



Soluble baryta . 



, . -724 



Insoluble (barytes ?) . 



. . 1-728 



Binoxide of manganese . . 



, . 84-620 



92965 



which show that the mass consisted chiefly of pyrolusite. That 

 the associated mineral was psilomelane follows from its appear- 

 ance and hardness, the colour of its powder, and the amount of 

 water contained, which is too little for manganite, and too much 

 for any of the other manganese minerals. 



The researches of MM. Deville and Debray (given in abstract 

 in the ' Chemical News/ vol. i. p. 299) show that natural binoxide 

 of manganese is a very complex substance, containing various 

 soluble salts, among which are alkaline nitrates, and that nitric 

 acid is one of its products of ignition. I have found the Teny 

 Cape pyrolusite to give strongly acid fumes on ignition, no doubt 

 from the presence of nitric acid. The nature of the soluble salts 

 I have not inquired into further than regards iron and baryta. 

 As a new illustration of the complexity of the mineral, it is an in- 

 teresting fact that silver, to the amount of five ounces to the ton 

 of ore, has been found in a specimen from Teny Cape, on assay 

 by J. Taylor and Co., in London. I may here recall the fact 

 that thallium to the extent of 1 per cent, has been detected by 



