THE 

 LONDON, EDINBURGH, and DUBLIN 



PHILOSOPHICAL MAGAZINE 



AND 



JOURNAL OF SCIENCE. 



[FOURTH SERIES.] 



FEBRUARY 1863. 



XII. On the Formation of Alpine Valleys and Alpine Lakes. 

 By John Ball, M.R.I.A., F.L.S. #c* 



EVERY one who feels an interest in the past history of the 

 Alps must be glad to find renewed attention given to the 

 natural agencies that have given that region its existing confor- 

 mation. Many persons will therefore have read with satisfac- 

 tion the papers recently published by Professor Ramsay, the 

 President of the Geological Society, in the Quarterly Journal of 

 that Society for August 1862, and by Professor Tyndall in the 

 Philosophical Magazine for the following month. To these 

 should, perhaps, be added some important observations con- 

 tained in an address delivered at the recent Meeting of the 

 British Association, by Mr. Beete Jukes, the President of the 

 Geological Section. In these publications by eminent English 

 men of science, the views of preceding alpine geologists, such 

 as Charles Martins, Gastaldi, and Omboni, which have been ably 

 summed up and extended in some recent memoirs byM.Mortillet,' 

 have received a still wider extension, and we are called upon to 

 enlarge very much our previous conceptions as to the agency of 

 those great glaciers which, at a period geologically very recent, 

 descended from the flanks of the higher Alps to the level of the 

 plains. 



If controversies in science were decided by the authority of 

 eminent names, or if the discussion of the problems raised by 

 these papers required a complete acquaintance with the whole 

 field of physics and geology, I should certainly not enter the 

 lists against such formidable opponents. The problems in ques- 

 tion, however, occupy a limited field in the region which is 



* Communicated by the Author. 

 Phil Mag. S. 4. Vol. 25. No. 166. Feb. 1863. G 



