Scientific Reviews. 123 
deposits, of most modern origin, whose discovery has only sprung 
from the tide of researches induced by an appeal to the assistance 
of other branches of observation, and which have tended so much 
towards elucidating the theory of the latest catastrophes, and the 
succession of organic creations ; the mind might be led much astray 
by granting a constancy of character which merely exists in the de- 
‘scriptions, and by neglecting those interposed beds which most. of 
all served to establish a difference between the epochs of the depo- 
sition of these mineral strata, of the origin of whose fossils we are 
still uncertain. Thus, above the gypsum with bones, we have blue 
clays, limestones, oyster beds, marls with menelites, schiste hap- 
pante, &c. &c. Erom the descriptions given of the upper fresh 
water formations, we should have much difhculty in recognizing 
the yellowish white marl of the Isle of Wight ; the argillo-ferrugi- 
nous sand, marl, and silicious meuliere, filled with cavities with 
shells of the plateau of Montmorency ; or the silex, marl, and com- 
pact limestone of the chateau Landon ; but an error applicable to 
one series of formations, when views no more practical have 
guided the delineation of the remainder, will be found repeat- 
ed throughout, leaving it an undeniable fact, that the geologist 
could seldom, from the mineralogical description of rocks which are 
contained in these elementary works, pursue his studies with any 
chance of success, unless indeed nature had supplied him with that 
talent for filling up minor details, which could alone spring from a 
facility of conception which it is wrong to suppose to be possessed 
by every beginner whose steps we propose to guide, or to spring 
naturally from the perusal of the great features of a science, of 
which we have intended to write a system. 
We have finished with our criticisms upon these volumes ; for, 
viewed in another light, they are works worthy of attentive peru- 
sal. . As an introductory outline to one of the most extensive and 
most interesting of the sciences of observation, Professor Brande’s 
work is peculiarly well adapted ; it is embellished with interesting 
and sometimes valuable wood-cuts ; his views on theoretic subjects 
are impartial and devoid of prejudice ; and his picture of the pre- 
sent state of things is very fair. 
“ If we look upon the landscape that surrounds us, we every 
where discern the fingers of that ‘ slow but sure destroyer, Time,’ 
busy in modifying the present aspect and appearance of things. 
The bold and rugged outline of the mountain chain, full of broken 
peaks, abrupt precipices, extensive rifts and caverns,—the deepen- 
ing of the valley beneath, covered with a fertile soil, brought down 
by the neighbouring streams, and beund together and enriched by 
organic remains,—the rapid and disturbed river expanding into the 
calm and undisturbed lake, whence it again issues, as it were, in 
renovated purity, and with new powers of fertilization,—are so 
many monuments of the devastation which a former order of things 
has suffered, and the records of the changes that are now going on.” 
— Out. of Geol. p. 193. 
