190 Revieivs — Alph. Favre's Geological Researches 



manner.- As it was said of de Saussure, who first grappled with the 

 physical obscurities of this region, that " he was one of the men privi- 

 leged by Providence to trace the road to new conquests," so we may 

 say of his countryman and successor, Alphonse Favre, that in follow- 

 ing his great master he has wrested from this complex region many 

 important revelations unknown to his predecessors. To take one 

 striking example of his successes, nothing can be more creditable to 

 him than the clear and skilful explanations and diagrams with which 

 he has taken a leading part in clearing up the long mooted question 

 as to whether or no the fossil plants of the old Carboniferous period, 

 in Haute-Maurienne, and at Petit Coeur in Savoy, lived on to the 

 age of the Lias : it being now generally admitted that the strata of 

 these two widely different formations, having been accidentally col- 

 located, have been so twisted up by convolutions as to appear to 

 belong to one and the same geological mass.^ 



On the other hand, the candour with which the author acknow- 

 ledges a mistake in his earlier researches, by which he placed a 

 Secondary limestone above the Nummulitic rocks, is so ingenuous, 

 that we quote the passage as a valuable reminder to all working 

 geologists, who well know that during their career they will have 

 to acknowledge many such an error. " Mais ce qui me console (says 

 he) d'etre classe parmi ceux que les terrains des Alpes ont entraine 

 a faire certaines confusions, c'est la nombreuse et bonne societe dans 

 laquelle je me trouve" (vol. ii. p. 33). So numerous, indeed, are 

 the points of confusion, that no historian of the geological succession 

 in the Alps can perform his task rightly and completely, if he has 

 only viewed the complicated region so well examined by M. 

 Favre. In it there do not exist any recognizable Palaeozoic rocks 

 of higher antiquity than the Carboniferous ; and of these, portions only 

 of clearly defined zones are to be here and there detected among the 

 crystalline and metamorphic masses of the broken ridges. It is a 

 region, in short, without any recognizable fundamental rocks; 

 the lowest and axial masses being disguised by heat and change. 

 Hence it follows that if in the Central, and particularly in the Eastern 

 and Central Alps, the disarranged strata had not been reduced to 

 order, and the real Palaeozoic succession recognized, the geological 

 history of the whole chain would have had no true beginning. In 

 other words, had it not been already shown that in those Eastern 

 Alps there existed Silurian, Devonian, and Carboniferous animal 

 remains, the key to a true historical succession of the whole 

 chain would not have been obtained. Yet, though the work in 

 question deals with the most broken and complicated poi-tion of 

 the chain, the manner in which M. Favre has unravelled this record 

 does him infinite credit. 



M. Favre gives also a very complete summary of every contribution 



1 See also a just and highly favourable estimate of this work as given by Professor 

 Studer, in Archives des Sciences Physiques et Naturelles, No. 121, Fevrier, 1868. 



2 In the opinion of the geologists of the Geological Society of France who visited 

 this tract, the views of M. Favre were fully sustained ; and the area of observation 

 considerably extended.— See Bull. Geol. Soc. de France, vol. xxii. p. 59, 1864-5. 



