568 Reviews — Professor Doelters Mineralogy. 



Canadian Pacific Railway, that mining operations were commenced. 

 Curiously, however, the mines were first worked for copper (the 

 principal nickel - producins: firm still being the Canadian Copper 

 Company), but it was soon found that the presence of nickel interfered 

 with the extraction of the copper ; and, indeed, it was not until about 

 that time that nickel came to have any commercial value. Detailed 

 descriptions are also given of the methods of mining, of the mechanical 

 treatment of the ores, and of the metallurgical processes. The occur- 

 rence and treatment of nickel ores in other parts of the world, 

 principally in New Caledonia and Norway, are also dealt with. 

 Finally, there is a short account of the uses of nickel in coinage 

 (though not in Canada), but particularly in nickel-steel and other 

 alloys. No mention is, however, here made of the extensive use of 

 nickel salts in electroplating. 



Y. — Peofessok Doelter's Mineralogy. 

 Handbuch der Mineralchemie. By Hofrat Prof. Dr. C. Doelter. 

 Bd. Ill, i, pp. 1-160. 8vo. Steinkopf : Dresden and. Leipzig. 

 Price 6.50 marks. 

 rriHE first part of the tliird volume of this work deals with the 

 _L oxides of titanium, zirconium, niohium, tantalum, and their 

 compounds with silica. The quantitative separations nnd estimations 

 of these oxides present many problems of grave difficulty to the 

 chemist. The various methods in use are described and discussed by 

 Dr. K. Peters, in addition to which there are special articles on the 

 analj^sis of lavenite, eudialyte, johnstrupite, and catapleite by 

 Dr. R. Mauzelius, and on the analysis of euxenite by Dr. G. T. Prior. 

 Dr. R. Pribram contributes a section on the chemistry of germanium 

 and the minerals in which it occurs. 



A very interesting chemical problem is the composition of the 

 rare mineral striiverite, which Dr. Prior has shown to be isomorphous 

 with ilmeno-rutile : both minerals are regarded as solid solutions of 

 tapiolite or mossite (iron tantalate and niobate) in rutile. It is 

 suggested that the name striiverite be reserved for those members of 

 the series in which tantalic acid preponderates over niohic acid, those 

 richer in the latter being called ilmeno-rutile. The determination of 

 both tantalum and niobium in the presence of large amounts of 

 titanium thus becomes a problem of great importance: this problem 

 has now been successfully solved by Hess and Wells in America and 

 more recently by S. J. Johnstone in London. 



Another group of minerals of great interest are the three forms of 

 titanium dioxide ; rutile, anatase, and brookite. To account for the 

 existence of these three forms many theories have been advanced ; 

 these theories still await definite proof, for while recent analyses of 

 rutile are fairly abundant, only two analyses of anatase and brookite 

 appear to have been made within the last fifteen years. The brookite 

 analysed by Kose in 1844 and said to have come from Snowdon, 

 "Wales, was doubtless from the well-known locality for that mineral 

 near Tremadoc. 



Professor Doelter himself has contribiited very largely to this part 



