PHYSICAL GEOLOGY. 195 



erratics from Wastdale Crag ; Chap. 29 with Praglacial River Chan- 

 nels, and the evidence they furnish of a continental period in Britain ; 

 Chaps. 30, 31 are devoted to the Theories of Glacier-motion. A. H. G. 



Deane, Gt. Cosmical Theories of the Earth. Pp. 29. Proc, 



Birmingham Nat. Hist. Soc. 

 A Retiring Presidential Address. 



Fisher, Rev. 0. On the Inequalities of the Earth's Surface, viewed 

 in connection with the Secular Cooling. Trans. Cambridge Phil. 

 Soc. vol. xii. pt. 2, pp. 20. 4to. 



Fritz, Prof. H. Aus der kosmischen Physik. [Cosmical Physics.] 



22 pp. 4to. Zurich. 

 Forms the new year s number of the Ziirich Society of Naturalists, 

 vol. Ixxvii. 



Green, W. L. Vestiges of the Molten Globe. Pp. 8, 59 ; 3 plates 

 (maps). 8vo. London, 



Herschel, Prof. A. S., and G. A. Labour. Report of a Committee 

 on Experiments to determine the Thermal Conductivities of cer- 

 tain Rocks, showing especially the Geological Aspects of the In- 

 vestigation. Hep. Brit. Assoc, for 1874, pp. 128-132. 

 Give the results of experiments on 19 kinds of rock. After tabula- 

 ting these observations and describing the mode of experimentation, a 

 preliminary attempt is made to frame a scale of rock-resistances to the 

 passage of heat. Erom the data arrived at, the reistances group them- 

 selves as follows : — A, Granite (with least resistance). B, Grit. C, Chalk. 

 D, Basalt. E,— ? F,— ? G, — ? H, — ? I, Shale. K, Coal and 

 Plaster of Paris (highest resistance). G. A. L. 



Kinahan, G. H. On the proposed Inundation of the Sahara. Jron, 

 vol. vi. p. 170. 



Considers it probable that the retreat of the snow-line in Europe 

 from its earlier low level to its present position was brought about by 

 the drying up of the sea that once occupied the Sahara desert, and 

 suggests that the proposed change might cause S. Europe to be en- 

 veloped in perpetual snow, and change the Rhine and Danube into 

 great glaciers. F. D. 



Landerer, Jose J. Introduccion al estudio sobre el origen del 

 granite y de la caliza. [Origin of Granite and of Limestone.] 

 Madrid. 



Considers that granite rocks were originally vitrified, and that 

 calcium was primitively deposited on the earth's crust as protoxide. 



Leigh, Dr. John. [Report of a Lecture by.] Jowni. App, Sd^ 



vol. vi. pp. 12, 13. 

 Treats of the history of the formation of the earth from the time of 

 its supposed incandescent state. 



o2 



