Prof. Struder on Bowlders. 327 



blocks, whose interstices were entirely filled lip with smaller 

 gravel and sand, which also occurred independently, in great 

 masses, as well over as underneath and along side the accumula- 

 tion of blocks. This chain of hills is manifestly the last remains 

 of a much more general overspreading of detritus, which has 

 been torn to pieces and carried away by later water-courses, A 

 glazier-mound (Gletscher-Gandecke) it is not, as I at first suppos- 

 ed, on becoming acquainted with the new veins, and Hr. v. Char- 

 pentier himself is the person who corrected my mistake ; as just 

 at the time of our visit to the diggings, clear traces were brought 

 to light of orderly arrangement and a quiet subsidence from wa- 

 ter. In the mean while, the difficulty, in which the masses of 

 smaller rubbish place us, will be no reason in geology, which has 

 grown hardened against difficulties of this kind, for rejecting the 

 whole theory of diluvial currents, in favor of which there are so 

 many other facts. Indeed we have only to suppose the original 

 lakes to have been some hundred feet larger in extent than at 

 present, and then we have surrounding our lakes considerable 

 plains and broad valley flats, which the eye at once perceives 

 arose from the emptying of earlier, much more extended lake 

 basins, and which have in fact received very large quantities of 

 that rubbish. 



The ingenious theory Hr. Yenetz has constructed, on the 

 phenomenon of bowlders, and which Hr. v. Charpentieb has 

 been able with so much acuteness to bring into consistency with 

 the more recent geological views, builds for the. blocks a bridge 

 of ice over the Swiss lowland and the abysses of her lakes and 

 has them sledded down by the advancing glacier, in rows (tra- 

 gen in Guferlinien) to its outermost limit, where they heap up 

 in ice-piles or glacier-walls. The glaciers, hitherto blocked up 

 on the back central chain, broke out from all the slope vallies 

 upon lower Switzerland, for the most part overspread it, and then 

 mounted to a considerable height up the Jura. The rubbing of 

 the ice occasioned the jags and erosions often visible to a great 

 height on the rocky walls of our slope vallies and which have 

 hitherto been regarded as evidence of the ancient water-courses. 

 And in order to support the assumption of so great a cooling of 

 the climate, a general elevation and distension of the whole Al- 

 pine region and its contiguous parts is presumed to such a height 

 as to sink the mean annual temperature of the lowland down to 



