1908] on Ice and its Natural History. 269 



quite sensible velocity. In fact, the antrum of the Glacier des 

 Bossons. in the summer of 1895, offered an example on a large scale 

 of a cold-pressed tube, of which the material was ice, which yielded 

 perfectly to continued pressure, while the rock was the resisting 

 button . 



It will be readily recosrnised that the scoring and groovinsr of the 

 ice surface by the opposing rock can be witnessed only when a glacier 

 is advancing, and, in summer, only in localities adequately protected 

 from melting agency. 



For years I imagined that I was the only person who had seen 

 glacial action thus reversed, but later, when I acquired Hugi's 

 works and after I had studied them carefullv, I found that he had 

 observed this, as well as almost evervthing else that it is possible to 

 see in a glacier. Before starting: on his memorable winter expedition 

 to the Eismeer, he had the position of the lower extremities of both 

 the upper and the lower glacier of Grin del wald exactly marked out, 

 so as to be able, on his return, to ascertain, by direct measurement, 

 any advance or retreat which had taken place. His way to the 

 Eismeer lay along the flank of the upper glacier which at that 

 date, January 1832, was advancinsr in great volume into the plain 

 where it spread itself out like a fan, and he observed that on its 

 western side the motion of the glacier was opposed by a mass of rock. 

 It pushed itself over this rock with great energy, and for a distance 

 of 41 feet down the valley the surface of the ice, which had passed 

 over the rock, was deeplv scored and s^rooved. It was observed that 

 the glacier shoved itself over the rock at the rate of 5 J or 6 inches 

 per day : it was also noticed that the ice on the eastern and opposite 

 side of the glacier hardly moved at all, not more than a few inches in 

 three weeks. It was, however, reported in the followinsr spring by 

 the man whom Hugi employed to observe the glacier daily, that in 

 February the western flank of tlie glacier became stationary, while 

 the eastern flank pushed forward, digging up great masses of stone 

 and earth. 



This passage, which I have reproduced at length, not only gives 

 valuable objective information about the glacier, it also enables us to 

 form a subjective appreciation of the man who, with nothing but the 

 stipend of a schoolmaster, was able to undertake an enterprise on so 

 large a scale and so difficult as a Wintprreisfi in das Eisiuper, and who 

 carried it out with such attention to detail as to have the two 

 principal glaciers which were fed by the Eismeer on which he was 

 going to sojourn for a fortnight kept under observation during the 

 whole winter. 



In comparing mv observation of the striation of the glacier by 

 the rock with that of Hugi, it will be noticed that his was made in 

 January, the coldest month of winter, and in the year 1882, when 

 the crlacicrs were in the plenitude of their power, while mine was made 

 in August, the hottest month of summer, in the year 1895, when 



