68 Proceedings of the Royal Society 
intelligent reasoner might have disregarded. It is professedly 
confined, for the most part, to the superficial formations, and to 
the basin of the Lake of Gleneva. But the author’s turn for dis- 
cursive illustration of his subject ever tempts him to introduce 
curious, and sometimes important facts, recorded by him in other 
countries, and in the older rock formations. The work, in fact, 
oscillates between a memoir on local geology and a systematic 
treatise ; and it does not exactly fulfil the purpose of either. The 
innumerable references which it contains to forthcoming parts of 
the intended work give us good room to regret that Necker had 
not more strictly followed the course pursued by his grandfather, 
De Saussure, by publishing his geological observations in the order 
in which they were made, and interspersing them with those con- 
tributions to the other parts of physical geography, and those 
animated descriptions of scenery, in which he, as well as his 
illustrious relative, peculiarly excelled. 
Even in its present fragmentary form there is much to interest 
the geologist in the isolated volume of studies which M. Necker has 
left. The followers of Sir Charles Lyell will find in it a fund of 
admirable observations on the effect of causes still in action ; and 
although the doctrines of glacial operation have made great pro- 
gress since 1841 ; and although Necker was systematically disin- 
clined to side with those who attributed to the formerly vast 
extension of glaciers conspicuous effects both in and out of Swit- 
zerland, his information on the distribution of erratics in the basin 
of the Lake of Geneva is very interesting and suggestive, and 
many of the facts and difficulties which he propounds are worthy 
of great consideration.* 
As the Etudes sur les Alpes was the last, not only of Necker ’s 
larger and separate, but even (I believe) of his more occasional 
printed contributions to science, I may as well advert here to one 
or two of the latter — his detached memoirs — which I have not 
already had occasion to mention. There are several on subjects of 
pure mineralogy, perhaps of no great intrinsic importance. There 
is a paper in the Transactions of the Royal Society of Edinburgh, 
^ I have elsewhere pointed out (Edin. Review, April, 1842) some errors 
into which M. Necker fell in treating of the mechanism of glaciers, a subject 
to which he appears to have given but little attention. 
