RECENT ADVANCES IN SCIENCE 37 



by staining and other methods by E. Steidtmann (Bull. Geol. 

 Soc. Amer. 191 7, 28, 431-50) confirms the conclusion arrived 

 at along other lines, that most dolomites are of marine origin, 

 and that only a minority were formed by the replacement of 

 limestone by the action of underground waters. 



Tarr, W. A., Origin of Chert in the Burlington Limestone, 

 Amer. Journ. Sci. 191 7, 44, 409-52. 



Daly, R. A., Low Temperature Formation of Alkaline 

 Feldspars in Limestone, Proc. Nat. Acad. Sci. 191 7, 3, 659-65. 



Macnair, P., Notes on the Microscopical Characters of the 

 Blackbyre Limestone in the West of Scotland, Trans. Geol. Soc. 

 Glasgow, 191 7, 16, 290-304. 



Ries, H., A Peculiar Type of Clay [composed mainly of 

 dolomite rhombs], Amer. Journ. Sci. 191 7, 44, 316-8. 



Geological Processes. — E. S. Moore describes the activity 

 and products of the five great active volcanoes, White Island, 

 Tarawera, Ruapehu, Ngauruhoe, and Tongariro, in the North 

 Island of New Zealand (Journ. Geol. 191 7, 25, 693-714). They 

 are situated along an almost direct N.N.E. line, following a 

 fissure zone of immense size, which may be continued through 

 Tonga and Samoa to Hawaii. The volcanic activity began in 

 the Middle or Lower Miocene, but the main eruptions appear 

 to belong to the Pliocene. 



In discussing the origin of calcite and gypsum veinlets in 

 the Silurian and Devonian strata of Central New York, S. 

 Taber (Journ. Geol. 191 8, 26, 56-73) comes to the conclusion 

 that they were not deposited in pre-existing openings, but 

 made room for themselves by rending apart the enclosing 

 walls. The necessary energy was supplied by the molecular 

 forces associated with the separation of solids from solution. 



In two papers on the coral reef problem Prof. E. W. Skeats 

 discusses the evidence of the Funafuti borings and the bearing 

 of the formation of dolomite upon that question (Amer. Journ. 

 Sci. 191 8, 45, 81-90 ; 185-200). He concludes that the nature 

 of the organisms, the rock-textures of the Funafuti bores, and 

 the submarine contours of the island, are only explicable on the 

 subsidence theory of Darwin. This view is supported by cogent 

 evidence of the shallow-water origin of dolomite, and the 

 dolomitisation of many coral reefs. 



In an instructive paper on the transportation of debris by 

 icebergs (Journ. Geol. 191 8, 26, 74-81), O. D. von Engeln makes 



