Eevieics—The Gold Mines of the Rand. 671 



III.— The Gold Mines op the Eand, being a Desoeiption of 

 THE Mining Industry of Witwateksrand, South African 

 Republic. By Frederick H. Hatch and J. A. Chalmers. 

 (London : Macmillan and Co., 1895. Price 17s.) 



THAT a mining district which produces gold to the value of 

 £6,963,000 sterling per annum, and the market value of 

 whose mines is over £100,000,000, should so long remain' without 

 any work descriptive of the nature of the industry and the geological 

 structure of the country, is remarkable. 



Messrs. Hatch and Chalmers' book on the "Gold Mines of the 

 Eand " will be found to contain a brief description of the geology 

 of the district and a more extended account of the mines, the method 

 of mining employed, and two useful chapters on the metallurgical 

 treatment of the ore, including the history and application of the 

 cyanide process. The work is copiously illustrated and is acconi- 

 panied with a geological section, two maps of the chief mining 

 centres of the Southern Transvaal, and several tables showing the 

 monthly output of the mines, dividends paid, etc. 



The authors have put together, in a very readable form, a mass of 

 information that has been gradually accumulating on the subject. 



The chapters on the geology of the district are confined to a brief 

 account of the geological structure of South Africa, a description 

 of the auriferous conglomerates, and some remarks on the nature of 

 the mineralization, the origin of the ore bodies, and the distribution 

 and value of the gold contents. 



The South African formations are broadly grouped together in 

 descending order as follows : 



Recent deposits. 



Karoo formation. 



Cape formation. 



South African Primary formation. 



The Witwatersrand beds (following Schenck) are assigned to the 

 Cape formation, but no new facts are brought forward to support 

 this view. 



Some errors that have appeared in nearly all descriptions of the 

 geological structure of the country are repeated. Thus the quartzites 

 and shales to the immediate north of Johannesburg are represented 

 on the diagram section as having the same dip as the aurilerous 

 conglomerates, whereas they are only locally conformable, though 

 the strike of the two groups is coincident from east to west. There 

 is little doubt that the junction of the gold-bearing beds and the 

 quartzite shale group is a faulted one, and that the true sequence 

 remains to be discovered. 



The relation of the "Banket beds" to the Primary formation is 

 also not clearly stated, but it is inferred (p. 71) that they rest on 

 the eroded edges of the latter. Near Johannesburg and again near 

 Yredefort there is very clear evidence that the Banket beds are 

 pushed over the ancient metamorphic rocks, while there is no 

 evidence to show that the conglomerate beds were formed by the 



