554 SCIENCE PROGRESS 



46, 591-8) a» original marine sediments ; and their constant 

 oolitic texture is believed to be closely connected with their 

 origin. The waters in which they were deposited were warm, 

 shallow, and bordered by low-lying land contributing little or 

 no terrigenous material to the sediments. Phosphatisation 

 was accomplished by solutions derived from decaying organic 

 matter at a period subsequent to the formation of the oolites. 



In an exhaustive memoir (" Monograph on the Consti- 

 tution of Coal," Dept. of Set. and Indust. Research, 191 8, pp. 58) 

 M. C. Stopes and R. V. Wheeler conclude that coal is a mass of 

 morphologically organised plant tissues, with other unorgan- 

 ised plant substances such as resin, mingled with the com- 

 minuted degradation products of tissues and cells, or such 

 products in the form of members of the ulmin group. Not 

 only are resistant tissues preserved, but also much more delicate 

 structures, provided that they are immersed at an early stage 

 in the aseptic matter arising from a special kind of breakdown 

 of plant tissues. 



Economic Geology. — The new Geological Survey volume of 

 Special Reports on the Mineral Resources of Great Britain 

 (vol. vii. Mem. Geol. Surv. 191 8, pp. 6y) deals with lignites, 

 jets, the Kimmeridge oil shale, mineral oil, cannel coals, 

 and natural gas. In view of the rumours, " more or less 

 ill-founded, as to the existence of copious untapped sources " 

 (see Preface) of mineral oil in Britain, the warning paragraph 

 on p. 41 dealing with the occurrence of mineral oil in Derby- 

 shire should be read in connection with V. C. Illing's con- 

 vincing article on " Borings for Oil in the United Kingdom " 

 {Nature, Jan. 16, 1919, 385-8), in which is demonstrated the 

 great geological improbability of oil being struck in commercial 

 quantity in the borings now being sunk or projected in various 

 parts of the country. An anonymous article in the Glasgow 

 Herald (Shipbuilding, Engineering, and Commerce in 191 8, 

 Dec. 28, 191 8) on Oil Fields, British Resources, takes prac- 

 tically the same view. 



Wagner, P. A., Mineral Oil, Solid Bitumens, Natural 

 Gas, and Oil Shale, South African Journal of Industries, 

 Industrial Bull. Ser. No. 3, Oct. 191 7 (1918), pp. 29. 



Clements, J. M., Petroleum in Japan, Econ. Geol. 191 8, 

 13, 5 1 2-23. 



G. S. Rogers discusses the origin of the great salt domes 



