5 6S SCIENCE PROGRESS 



A. M. Bateman proposes a modification of E. Howe's theory 

 that the nickel ore was intruded in a molten state (Econ. Geol. 

 191 7, 12, 391-426). He believes that the intrusion of the 

 Sudbury norite took place in two stages, the first of which 

 gave rise to the " nickel eruptive," the second to the southern 

 granite and finally the differentiated ore, which was partly 

 re-arranged by subsequent hydrothermal action. This view 

 is intended to reconcile the unassailable elements in the con- 

 flicting theories mentioned above. In a short paper Coleman 

 vigorously defends the theory that the nickel ore has resulted 

 from the gravitative differentiation of the Sudbury norite 

 micropegmatite sheet (Econ. Geol. 191 7, 12, 427-34). He 

 makes strong points of the world-wide association of nickel 

 ores with this kind of igneous rock ; and of the absolutely un- 

 weathered character of the enclosing igneous rock in normal 

 cases where faulting and subsequent re-deposition has been 

 inoperative, a feature inexplicable on the theory of hydro- 

 thermal replacement. 



Two useful statistical compilations by G. C. Lloyd (" Report 

 on the Resources and Production of Iron Ores and other 

 Principal Metalliferous Ores used in the Iron and Steel Industry 

 of the United Kingdom," Advisory Council, Dept. of Scientific 

 and Industrial Research, 191 7, pp. 145), and W. G. Fearnsides 

 (" The Mineral Requirements of the British Iron and Steel 

 Industries," Trans. Soc. Engineers, 191 7, pp. 7-109) summarise 

 the available resources of iron ores and other materials used 

 in British iron and steel production, especially in view of war 

 conditions. British coalfields are receiving close attention 

 just now, as shown by the publication of a second edition of 

 Part 4 of the Geological Survey Memoir on the geology of the 

 South Wales coalfield (A. Strahan et alia, " The Country 

 around Pontypridd and Maesteg," Expl. of Sh. 248, 191 7, pp. 

 160), and of a further instalment of the results of the revision 

 of the central coalfield of Scotland (R. G. Carruthers and 

 C. H. Dinham, "The Economic Geology of the Central Coalfield 

 of Scotland : Area VIII. East Kilbride and Quarter," Mem. 

 Geol. Survey Scotland, 191 7, pp. 52). 



T. C. Cantrill describes a boring made for coal in Silurian 

 rocks near Presteign, Radnorshire (Geol. Mag. 191 7, 4, 481- 

 92). In spite of his warning that the rocks contained no coal, 

 the promoters persisted in sinking the bore to a depth of 



