440 



NATURE 



[September io, 1896 



be due to cooling and contraction leading to subsidence as 

 suggested in page 34, it is evident, though, so far as I am aware, 

 this has not hitherto been pointed out, that, as already suggested, 

 the compression and consequent folding of the strata (Fig. 43) 

 would not be in the direction of A I! only, but also at right 

 angles to it, in the direction AC, though the amount of folding 



Fig. 43.— Di: 



illustration of 



might be much greater in one direction than in the other. Thus 

 in the case of Switzerland, as the main folds run S.W. and N. E., 

 the subsidiary ones would be N.W. and S.E. If these consider- 

 ations are correct it follows that, though the main valleys of 

 Switzerland have been immensely deepened and widened by 

 rivers, their original cause was determined by tectonic causes " 

 (pp. 149, 150). 



Thus the chief distinction previously made by the 

 writer between longitudinal and transverse valleys is 

 finally annihilated by his own suggestion that both may 

 have had their primal cause in tectonic movements I 

 But this idea finds by no means its first exponent in Sir 

 John Lubbock. It is perfectly familiar throughout the 

 writings of .'\ustrian and German geologists. Take the 

 following passage, which I translate from Rothpletz : — 



" As the youngest expression of the iitountaiu-formUig forces, 

 these (the transverse faults) have had a specially important 

 influence on the present topography of the mountains, the 

 direction of the flowing waters, and the origin of lake-basins. 

 It is to them above all that the longitudinal synclinal folds of 

 the Alps owe the outflow of their waters by transverse valleys ; 

 and the length of high ridges of rocks has been determined by 

 them." ("Kin geolog. Querschnitt durch die Ost-Alpen." 

 Stuttgart, 1S94, p. 190.) 



The stratigraphical facts observed by these geologists 

 somewhat modify the theoretic suggestion of Sir John 

 Lubbock. They prove that the transverse lines of weak- 

 ness, whether of simultaneous origin or not with the 

 longitudinal folding, were planes of movement long after 

 the longitudinal folds had ceased to move, i.e. had 

 become in technical language " dead " folds. // is this 

 relative youth nf the traitsi'erse faults which has made 

 ihem so often rcvolutionisers of Alpine drainage. We 

 would certainly have expected to have this important 

 matter looked into by Sir John Lubbock, especially as he 

 has devoted considerable space to minute matters of 

 drainage in the three succeeding chapters on the "Action 

 of Rivers," their " Direction," and " The Lakes." 



With regard to the vexed C|uestion of the excavation of 

 the lake-basins by glaciers, Sir John Lubbock states that 

 "there are strong reasons against regarding glaciers as 

 the main agents in the formation of the great Swiss and 

 Italian lakes " (p. 210). The general reader may learn 

 inuch from the chapter on " Lakes." 



A \ cry important subject is then introduced in Chapter 

 3L — "The Influence of the Strata upon Scenery." If I 



NO. 1402, VOL. 54] 



may prophesy, this is the " coming " theme in popular 

 geology. Combining as it does the interest of beauty of 

 form with that of varied natural phenomena, it appeals 

 alike to artist or tourist, geographer or petrographer, 

 physicist, chemist, or geologist. This, I repeat, is at once 

 the grandest, the most striking, and the most popular 

 department of the Science of Scenery ; and, what is more, 

 the student of it would rightly choose Switzerland for his 

 field of study in preference to any other country in 

 Europe ! Yet Sir John Lubbock has devoted only one 

 chapter of twenty pages to this subject, and has treated it 

 in a meagre, perfunctory manner. Only one sketch-section 

 by Baltzer illustrates this extensive subject. The reader 

 who brings enthusiasm to the book, and has Alpine 

 pictures in his eye, will stir life into the bare facts, but the 

 reader who has not will fail to be impressed. 



All the subsequent chapters from xi. to xxv. are 

 geological in their bearing, and take up the districts of 

 Switzerland in turn. The geology of the Jura mountains 

 is sketched in simple, clear style in Chapter xi. The 

 Miocene and Glacial deposits of the " Central Plain" of 

 Switzerland are described in Chapter xii. The next, 

 entitled "The Outer Alps," is one of the best in the book. 

 It runs easily along and describes, amongst other things, 

 the geology of the ever-fascinating Rigi and its proud 

 rival Mount Pilatus. One almost regrets that the chapter 

 should be brought to its close in the cloud of controversy 

 which overhangs the history of the " Klippen." The 

 chapter on " Central Massives " is rather overladen with 

 the opinions of many geologists, but concludes by regard- 

 ing the Central Massives (i) "as an integral part of the 

 general Alpine system, not as independent centres of 

 upheaval ; and (2) as complex systems of compressed 

 folds " (p. 307). 



Chapter xv., "The Lake of Geneva" is, like Chapter 

 X., a sacrifice to science — useful, instructive, practical, 

 but written with a marked economy of the imagination. 

 Surely the most prosaic Englishman who has seen the 

 view of the mountains from the northern side of the lake 

 must remember it all his days, and feel the very words 

 " Lake of Geneva " act like a charm upon him. This 

 chapter in the " Scenery of Switzerland " commences as 

 follows : — 



" The Lake of Geneva is 45 miles in length, and about 10 in 

 breadth. It is 375 metres above the sea, or 309 m depth. 



"The bottom, moreover, is covered by subsequent deposits to 

 an unknown depth, so that originally it was probably below, 

 perhaps much below, the sea-level. Indeed, if the slopes of the 

 mountains at Meillerie and Vevey (see Fig. too) are continued 

 under the bed of the lake, the alluvium must have a thickness of 

 no less than 600-S00 metres, which would make it 200-400 

 metres below- the sea-level. The actual outlet at Geneva is in 

 superficial debris, but the river comes upon solid rock at Vernier, 

 1197 feet above the sea-level, 33 feet therefore below the surface- 

 level of the lake, and 951 above the bottom. It is, therefore, a 

 true rock basin " (p. 308). 



The same conclusion is arrived at in the same matter- 

 of-fact way about other lakes, e.g. Lake of Neuchatel 

 (p. 259), Lake of Constance (p. 414). There are some 

 graceful touches however ; — 



" The country about Vevey and Montreux is the Riviera 01 

 Switzerland. It is lovelv now, but what must it have been 

 before the monotonous terraces of the vineyards and the endless 

 rows of vine bushes replaced the ancient forests of chestnut, 

 birch, and beech ; and the picturesque Swiss chalets were 

 extinguished by whitewashed villas and gigantic hotels " (p. 310). 



"The Massif of Mont Blanc," Chapter xvi., again falls 

 distinctly short of the sublimity of the subject. Is it so 

 necessary to begin with exact figures .' 



" ' The Massif of Mont Blanc' is elliptical in outline, about 

 30 miles in length, and 10 in breadth, extending from S.W. to 

 N. E. from the Col de Bonhomnie, across the Valais at Martigny 

 to the Dents de Morcles ; the extreme N. E. portion being severed 

 from the rest by the Rhone" (p. 322). 



