184 Scientific Intelligence. — Geology. 



imaf^ined, but that, immediately at tlie foot of these hills, lay ex- 

 tensive plains of mud and sand, at times evidently flooded by the 

 sea, for on them lay dead shells of many kinds and sizes, as well as 

 large travelled blocks of coral. The water now appeared to be 

 about a mile distant ; it was apparently boundless in an easterly 

 and north-easterly direction, and was studded with islands. We still 

 felt convinced that it was water we saw, for the shadows of the low 

 hills near it could be distinctly traced on its unruffled surface. As 

 we continued to advance, the water, however, constantly retreated 

 before us, and at last surrounded us. We had been deceived by 

 mirage ! — The delusive appearance of water of the desert. 



GEOLOGY. 



5. Agassi^ Tour to the Swiss Glaciers. — After the Bern meeting, 

 I went with Studer to Monte Rosa and to the Matterhorn, and af- 

 terwards, when he proceeded to Piedmont, I visited the Aletsch 

 glacier behind the Jungfrau, then the Rhone glacier, and finally ex- 

 tended my expedition as far as Hugi's hut on the Aar glacier. I 

 found my previous observations everywhere confirmed, and in- 

 tend publishing a full account of the results of my tour. I have 

 had sketches drawn by a skilful artist who accompanied me, so 

 that I shall be able to give faithful representations of all the phe- 

 nomena. The most important new fact which I have observed 

 is, the forward movement of Hugi's hut. Since the year 1827, it 

 has advanced upwards of 4000 feet. In 1830, Hugi found it some 

 hundred feet from the spot where it was built; in 1836, it was 

 above 2000 feet from it; but this year I found it removed to a dis- 

 tance of 4000 feet from its original position, and still the glacier is 

 very little inclined, and the mass pressing from behind is very in- 

 considerable compared with the lower mass, so that the explana- 

 tion of the progressive movement of glaciers, by sliding and pres- 

 sure from behind, goes for nothing. I recommend every one who 

 wishes to learn any thing of glaciers, to examine more particularly 

 the Lower Aar glacier and the glaciers between l^lonte Rosa and 

 the Matterhorn. But the Aletsch is the most imposing, on account 

 of its great size and the frightful desolateness of its vicinity. No- 

 thing can surpass the polish of the Serpentine over which the Gorn 

 glacier is advancing or has advanced. Hugi's hut prove;:, in the 

 most distinct manner, that the deeper the glacier the more rapid is 

 its movement. During this journey, my friends Desorand Nicolet 

 likewise accompanied me, so that the observations were not merely 

 made but were fully discussed. I think that I could now convince 

 any one, who would accompany me for a few weeks to the Alps, 

 of the correctness of my views ; and as I propose visiting them 



