ECONOMIC GEOLOGY. 195 



Notices various stones used for decorative purposes. The Mexican 

 stone is a marble (essentially carbonate of lime) of very many colours, 

 and is said to be " of stalagmitic origin, formed by running water." 

 A qualitative analysis is given. The quarry is at Tecali, 35 miles 

 from the city of Mexico. The largest block yet shipped measured 

 10x5x4 feet. W. W. 



Easton, Edward. On the Yield of Wells sunk in the Chalk in the 

 central portion of the London Basin. Proc. Inst. Mecli. Eng. 

 pp. 1G3-109, 3 pis. (2 Geological, 1 Rainfall and Level of Water 

 in Wells), Discussion, pp. 169-176 ; and Iron, n. s. vol. vii. p. 585. 



Discusses the disturbing causes influencing the flow of underground 

 water, especially the fault (or faults) in the Thames valley E. of 

 Deptford, and the fissures of the Chalk. Disturbing causes render the 

 finding of water very uncertain. The flow of water through the Chalk 

 to the weUs at Brighton is described. Where wells are sunk through 

 the Tertiary sand into the Chalk, a large part of the water in the wells 

 comes from the sands — as is sometimes proved in the well itself, and at 

 other times may be inferred from analyses. No very large quantity 

 of water can now be obtained from the Chalk beneath London ; addi- 

 tional supply for London must be looked for in outlying districts, where 

 the Chalk comes to the surface. W. T. 



Fenzl, Jelinek, v. Schroetter, Stefan, and Suess. Report of the 

 Special Committee for the consideration of the memoir of Hr. 

 Hofrath G. Wax upon the diminution of the water of Rivers 

 and Streams. Translated in Ann. Bejp. Smithson. Inst. pp. 198- 

 204. (See notice of the original in the Geological Recobd for 

 1875, p. 205.) 



Gamble, J. G. The Brighton Intercepting and Outfall Sewers. 



Proc. Inst. Civ. Eng. vol. xliii. pp. 191-203. (Discussion, pp. 204- 



224.) 

 Geology, p. 192 ; amount of water pumped from the Chalk, pp. 200, 

 201. 



Geikie, Prof. A. Outlines of Field-Geology. With an Account of 

 the Use of Surveying Instruments, and the Construction of Geo- 

 logical Maps. 8vo. London. Pp. 61. 

 Contains an explanation of maps, notes on the accoutrement of a 

 field-geologist, character of field-work, preliminary traverses, determi- 

 nation of rocks and fossils, tracing of boundaries, determination of 

 geological structure, construction of sections, ifec. II. B. W. 



Glinzer, Dr. E. Das Eisen, seine Gowinning und Vcfwendung. 

 Pp. vii, 106. 8vo. Hamburg. 



Granstrom, G. A. NSgra underrUttelser om grufvorna och gruf- 

 driften inom Xorbergs Vergslag. [Mines and Mine-workings in the 

 District of Norbcrg.J Jernkontords Anmdtr^ Arg. 31. tSiodholm, 



o2 



