Geology and Mineralogy. 403 



streams, and flowing southward until it abutted against the 

 mountains of* "Wales, was divided into two tongues, one of 

 which flowed to Wellington and Shrewsbury, while the other 

 went southwest across Anglesey into the Irish Sea. This great 

 glacier and its branches are all outlined by terminal moraines, 

 described in detail. A small tongue from it, the Aire glacier, 

 was forced eastward at Skipton and has its own distinctive mo- 

 raine. In the neighborhood of Manchester the great moraine of 

 this Irish Sea glacier may be followed through Bacup, Hey, Staley 

 Bridge, Stockport and Macclesfield, being as finely developed as 

 the moraines of Switzerland and America. South of Manchester, 

 it contains flints and shell-fragments, brought by the glacier from 

 the sea-bottom over which it passed. At Manchester the ice was 

 at least 1,400 feet thick, being as thick as the Rhone glacier. 



The great terminal moraine now described of the united gla- 

 ciers of England is a very sinuous line, 550 miles in length, ex- 

 tending from the mouth of the Huniber to the farthest extremity 

 of Carnarvonshire, and, except where it separates the Welsh 

 glaciers from the North Sea glacier, everywhere marks the ex- 

 treme limit of glaciation in England and is an important feature 

 which might well hereafter be marked on the geological map of 

 England. 



2. Les Eaux Souterraines a V epoque actuelle y Leur regime, 

 leur temperature, leur composition au point de vue du role qui 

 leur revient dans 1' economie de 1' ecorce terrestre ; par A. Datj- 

 beee. Membre de 1' Institut. 2 vols, of 456 and 302 pages, 8vo. 

 Paris, 1887. (Vve. Ch. Dunod.) 



Les Eaux Souterraines aux epoques Anciennes ; Role qui leur 

 revient dans l'origine et les modifications de la substance de 

 l'ecorce terrestre ; par A. Daubree. 483 pp. 8vo, Paris, 1887. 

 (Vve. Ch. Dunod.) 



These new works, by the eminent physical geologist of France, 

 M. Daubree, bear on some of the most interesting of geological 

 questions, and at the same time treat of subjects of wide economi- 

 cal importance. In the first of the two, the existing subterranean 

 waters considered by the author are those of wells, river sources, 

 caverns, artesian wells, saline waters, and mineral springs of vari- 

 ous kinds. The relations of wells and water sources to permeable 

 and impermeable strata are illustrated from special facts with re- 

 gard to superficial deposits, taken in part from the suburbs of 

 various cities, especially those of Europe and Great Britain ; and 

 also with a similarly wide range of facts, the author treats of 

 their dependence on the systems of fissures in rocks; on the junc- 

 tion planes of different rocks ; their relations to rocks of differ- 

 ent kinds, and of different geological periods; their connection 

 with the making of caverns ; their emergence as full-made rivers 

 from caverns ; their ejection from borings by different gases. 

 The discussion of these various subjects occupy the first volume of 

 456 pages. The second treats in a general way, without an array 

 of chemical analyses, of the substances held in solution by waters ; 



