LUBBOCK ON THE AKCIENT LAKE HABITATIONS OF SWITZERLAND. 49 



express our impressions, so to say, in terms of years, we are bafSed 

 by the complexity of tlie problem, 'aud cau but confess our ignorance. 

 Occasionally indeed we obtain a faint glimmer of light, but the result 

 is only to show us obscurely a long vista, without enabling us to de- 

 fine any well-marked points of time. Thus in Denmark we found 

 three periods of arborescent vegetation, corresponding to the three 

 epochs of human development, and we know that the extermination of 

 one species of forest tree and its replacement by another is not the 

 work of a day. The Swiss archaeologists, however, have attempted to 

 make an estimate somewhat more definite than this. 



Tlie torrent of the Tiniere* at the point where it falls into the Lake 

 of Greneva, near Villeneuve, has gradually built up a cone of gravel 

 and alluvium. In the formation of the railway this cone has been 

 bisected for a length of one thousand feet, and to a depth in the cen- 

 tral part, of about thirty-two feet six inches above the level of the rails. 

 Tlie section of the cone thus obtained shows a very regular structure, 

 which proves that its formation was gradual. It is composed of the 

 game materials (sand, gravel, and larger blocks) as are even now 

 brought down by the stream. The detritus does indeed difter slightly 

 from year to year, but in the long run the differences compensate 

 for one another, so that when considering long periods and the struc- 

 ture of the whole mass, the influences of these temporary variations, 

 which arise from meteorological causes, altogether disappear, and 

 need not therefore be taken into account. Documents preserved 

 in the archives of Yilleneuve show that in the year 1710 the stream 

 was dammed up and its course a little altered, which makes the 

 present cone slightly ii-regnlar. That the change was not of any 

 great antiquity is also shown by the fact that on the side where 

 the cone was protected by the dykes, the vegetable soil, where 

 it has been affected by cultivation, does not exceed two to three 

 inches in thickness. On this side, thus protected by the dykes, the 

 railway cutting has exj)osed three layers of vegetable soil, each of 

 which must, at one time, have formed the surface of the cone. They 

 are regularly intercalated among the gravel, and exactly parallel to 

 one another, as well as to the present surface of the cone, which itself 

 follows a very regular curve. The first of these ancient surfaces was 

 followed on the south side of the cone, over a surface of 15,000 square 

 feet ; it had a thickness of four to six inches, and occurred at a depth 

 of about four feet (1.14 metre measured to the base of the layer) 

 below the present surface of the cone. Tliis layer belonged to the 

 Eoman period, and contained lioman tiles, and also a coin. 



The second layer was followed over a siu'face of 25,000 square 

 feet ; it was six inches in thickness and lay at a depth of 10 feet 

 (2.97 metres, also measured to the bottom of the layer). In it have 

 been found several fragments of unvarnished pottery, and a pair of 

 tweezers in bronze, which to judge from the style belonged to the 



* See IMoiiot, Le^on d'OuvcrUirc, &c. 

 N. H. E.— 1862. E 



