RECENT ADVANCES IN SCIENCE 219 



subrang (II. 7, 2, 3) of the American Quantitative Classifica- 

 tion, which is consequently named baweanose. 



The rocks of the past and present flows of Sakura-jima, 

 Japan (see Koto B, reference under Dynamical and Structural 

 Geology) are, for the most part, hypersthene-, and hypersthene- 

 augite-andesites, occasionally also containing olivine as an 

 accessory. Numerous bombs of various gabbroid rocks were 

 also ejected. Bombs and lavas from Usu, Japan (see Oinouye, 

 reference under Dynamical and Structural Geology) are also 

 hypersthene-augite-andesites. These rocks appear to be over- 

 whelmingly predominant among the lavas of the present and 

 recent circum- Pacific volcanoes. 



The Mozambique " picrite " described by Holmes is a 

 dyke in gneiss ; and is almost identical with the picrite-basalt 

 lavas of Hawaii, and with the rocks called " felspathic picrite " 

 by Lacroix (see Science Progress, July 191 7, p. 32). 



Economic Geology 



HORWOOD, C. B., The Gold Deposits of the Rand; London (C. Griffin), 1917, 



pp. xx, 369. 

 Young, R. B., The Banket : a Study of the Auriferous Conglomerates of the 



Witwatersrand and the Associated Rocks ; London (Gumey & Jackson), 1917, 



pp. 125. 

 Waterhouse, L. L., The South Heemskirk Tin Field, Tasmania, Dept. of Mines, 



Geol. Surv. Bull. No, 21, 1916, pp. 450. 

 Brooks, A. H., Antimony Deposits of Alaska, U.S. Geol. Surv. Bull. 649, 1916, 



PP. 67. 

 Gregory, J. W., The Geology of Phosphates, and their Bearing on the Conser- 

 vation of Mineral Resources, Trans. Geol. Soc. Glasgow, 1917, 16, pt. 2, 



pp. 116-63. 

 Hume, W. F., Report on the Oil-fields Region of Egypt, Survey Dept. Egypt, 



1916, pp. 103. 

 Clough, C. T., et alia, The Economic Geology of the Central Coal-field of Scot- 

 land, Description of Area 5 (Glasgow East, Chryston, Glenboig, and Airdrie), 



Mem. Geol. Surv. Scotland, 191 6, pp. 146. 

 Mackenzie, J. D., Geology of a Portion of the Flathead Coal Area in British 



Columbia, Afem. 87, Geol. Surv. of Canada, 1916, pp. 53. 

 Rose, B., Wood Mountain— Willowbunch Coal Area, Saskatchewan, Mem. 89, 



ibid. 1 916, pp. 103. 

 Ransome, F. L., and Gale, H. S., Contributions to Economic Geology, Part I. 



Metals and Non-metals, except Fuels, Bull. 620, U.S. Geol. Surv. 191 6, 



pp. 361. 

 Hill, J. M., Notes on Some Mining Districts in Eastern Nevada, Bull. 648, ibid. 



1916, pp. 214. 



Mr. Horwood is a strong upholder of the infiltration as 

 opposed to the placer theory of the origin of the huge gold 



