July, 1893. ON THE WORK OF GLACIERS. 59 



ago as to the origination of the basin of the Lake of Geneva by the 

 pinching up of the valley of the Rhone, as an incident in the com- 

 paratively recent movements that have given to the Alps and the 

 Jura their present positions. 



There are some pertinent remarks to the same effect in Heim's 

 well-known " Mechanismus der Gebirgsbildung " ; and that writer 

 once for all disposes of the case of the Vierwaldstiittersee (Lucerne 

 Lake) by the results obtained by a series of soundings carried out by 

 himself and one of the engineers of the Federal Government ; since 

 these show conclusively that the bed of the lake is an alluvial plain of 

 an ancient valley, which has been converted into the present gem of 

 central Alpine lakes by a partial closure of the valley at the outflow 

 of the Limmat. The deep Achensee, again, is completely explained 

 by the facts which I gave ten years ago, as a case of a fault-originated 

 gorge, the drainage having been reversed as the great gorge of Jenbach 

 was dammed by the moraine stuff from a side-valley at Maurach.- 

 The Lake of Constance, again, is now well known to be a hollow 

 formed by the damming-up of an ancient valley by glacial detritus ; 

 the present " Falls of the Rhine " at Schaffhausen having originated 

 from a similar set of surface-changes to those which have produced 

 the Falls of Niagara, by diversion of drainage due to glacial obstruction 

 of the ancient valleys. Instance after instance of those quoted by 

 Ramsay and his school (even Ramsay's pet child, the Lake of 

 Llanberis) is being disposed of, as larger views of physiography are 

 made to bear upon the study of lakes. 



To go in detail into Dr. Blanford's criticisms would be but to 

 attempt to combat a scientific belief, which has been, to my mind, 

 rendered untenable by counter-arguments, based on known physical 

 and mechanical laws and observed facts. Until " geologists " will 

 take the trouble to go into the physical laboratory and master those 

 laws, and then show that my experimental work of ten years ago in 

 the Wellington College Laboratory upon the properties of ice, and 

 the conclusions to which it leads, as put forth in my paper on the 

 " Mechanics of Glaciers " {supra cit.) ; in the paper supplementary 

 thereto on " Solar Radiation and Glacier Motion " ; 3 in some criti- 

 cisms of a paper by another author which I published under the 

 title of the "Motion of Land Ice"*; and in the remarks which I 

 made two years ago under the head of " Dr. Nansen on Glaciation," 5 

 I feel that it is rather a " dealing of blows into the air " to enter into 

 controversy on these points. 



The phenomena of the recession of glaciers within the last century 

 or two, leaving a plain strewn with rolled detritus, and the draining' 



2 See my paper on the " Triassic Deposits of the Alps," Geo!. Mag., 1882, 

 p. 504. 



3 Nature, vol. xxvii., 1883. 4 Geol. Mag. for 1891, pp. 141-142. 

 5 Nature, vol. xliii., pp. 541-542. 



