Vol. 58. ] IN SUBALPINE FRANCE AND SWITZERLAND. 457 
(iv) The fact that the Deckenschotter-deposits occur on both 
sides of the Aare Valley, at Brugg, Turgi, and near the 
junction of the Aare with the Rhine, as well as on both 
sides of the latter river, warrants the further inference 
that, towards the end of the Pliocene Period, when the 
Deckenschotter was deposited, the Subalpine valleys of 
the Rhine, Aare, Limmat, and Reuss could not have 
existed in their present form and depth: the less so, when 
if is considered that the contact of the Deckenschotter 
with the underlying rock at those points is at about the 
500-metre contour, while the present Lakes of Zurich, 
Zug, Lucerne, and Neuchatel are respectively at contours — 
409, 417, 437, and 4385 metres. Even the Lake of 
Thun lies only at the 56(0-metre contour, that is, at a 
level which, to give a minimum ratio of fall from Thun 
to Turgi of 1 metre per kilometre (or 5} feet per mile), 
should be at least 230 metres higher.1 The same holds 
good with regard to the Lake of Constance, in relation to 
the deposits of Deckenschotter on both sides of the Rhine 
between Waldshut, Laufenburg, and Rheinfelden, where 
the contact of the conglomerate with the underlying rock 
varies between the 450- and 370-metre contours, while the 
lake-level is only at the 398-metre contour. The ratio of 
fall is thus totally inadequate: even according to the 
average fall of the present river,’ the difference of level 
should be at least 140 metres. 
IIT. Deposirs In tHE RuonE Vattny. (Figs, 6-12.) 
(1) In the Rhone Valley, the enormous accumulations of Glacial, 
Glacio-Fluviatile, and inter-Glacial material render the distinction 
between the products of the three glaciations much more com- 
plicated and difficult than in the North of Switzerland; the more 
so as, both in France and Switzerland, the geological maps still 
designate all the Glacial deposits indiscriminately as ‘ Quaternary ’ 
or ‘ Diluvium.’ It is due to French geologists, notably to F. Fon- 
tannes* and Fr. Delafond,* that the gravels and allied alluvia 
of South-eastern France were classified in ‘alluvions anciennes’ 
or ‘des plateaux’ (which were, however, regarded as pre-Glacial), 
‘alluvions des terrasses, and ‘alluvions des vallées’; a classification 
which, provided the Glacial or Glacio-Fluviatile origin of the 
‘alluvion ancienne’ be accepted, corresponds to the Decken- 
schotter, Upper- and Lower- Terrace Gravels, respectively, of 
Northern Switzerland. 
(2) About 5 miles north-east of Lausanne,’ not far from the road 
' The present fall = 230 metres in about 220 kilometres. 
2 The present fall = 140 metres in about 150 kilometres. 
* Bull. Soc. Géol. France, ser. 5, vol. xiii (1884-85) pp. 59 et seqq. 
* Ibid. ser. 3, vol. xv (1886-87) pp. 65 et seqg. 
> See footnote (') p. 459. 
