REPORT ON GEOLOGW 
405 
Elemens, De la Beche s Manual is the best work of this kind 
which has yet appeared in our own country. 
It is much to be regretted that while we find a general agree¬ 
ment as to the facts of the science in all these works, that agree¬ 
ment is sometimes obscured from the want of a simple and uni¬ 
form terminology of classification*, which should be generally 
adopted by geologists ; at present, indeed, such a terminology 
can be only considered as provisional, in as much as we are as yet 
only competently acquainted with the European series of forma¬ 
tions ; and it would be too hasty to pronounce that when those 
of the globe generally shall be equally known, many modifica¬ 
tions may not be required in our arrangements. Still I am per¬ 
suaded that the general adoption of some such confessedly pro¬ 
visional classification would materially advance the present in¬ 
terests of our science. 
A recent Essay of Boue’s, however, Considerations sur la 
Nature et sur V Origine des Terrains de VEurope, assumes a 
character of far higher philosophical speculation, than any mere 
systematic treatise on geological arrangement: from the dis¬ 
tribution and phenomena of each formation it endeavours to 
deduce the condition of the globe which prevailed at the period 
of its deposition, and the probable causes which concurred in 
its production. Leibnitz would have seen in it an able attempt 
to fill up in the detail from the results of geological investiga¬ 
tion, the history of those successive changes of the terraqueous 
crust, of which his powerful mind anticipated the general out¬ 
line. We may not, indeed, implicitly concur in all the views ad- 
* It would be one of the advantages of a scientific reunion, such as our present 
Society, if at some of our future sectional meetings such discussions were entered 
into, as might tend to promote this object; should any leading foreigners be 
present, such a design appears by no means chimerical. I have already sug¬ 
gested some occasional hints on this subject. I will venture here to submit to 
the attention of geologists the following sketch of a general classification, founded 
on an eclectic principle of borrowing from the works referred to in the text the 
arrangements in which they seem most likely generally to concur : as we have 
in other natural arrangements families, orders, classes, genera and species, so 
in geology we may have the aqueous and igneous families; the terms primitive, 
transition, secondary and tertiary, confirmed hy long use, may be retained for 
the four orders. The primitive would contain only the mica schistose group; the 
transition might contain three groups,—1, the clasmoschistose, or grauwacke ; 
2, the anthraxiferous, or lower coal measures; 3, the carboniferous. I include 
2 and 3, as does DTIalloy, in the transition order, being convinced, from the 
affinities of their organic remains, and every other relation, that such is their 
most proper place. 
The secondary order would include, 1, the pcecilitic group; 2, the oolitic; 
3, the cretaceous. The tertiary order has also three groups, for which Lyell 
has proposed the names Eocena, Meiocena, and Pleiocena. I would inquire 
however whether some such designations as hypotrital, mesotrital, and hyper- 
trital, would not be more simple. 
