398 Analysis of Scientific Books. 
' The nomenclature of most minerals is at present so incumbered with 
synonyma, that it has become extremely perplexing to the student. The 
mineral called epidote by Haiiy, is named pistazit by Werner, thallite by 
Lametherie, akanticone by Dandrada, delphinite by Saussure, glassy actylo- 
nite by Kerwan, arendalite by Karsten, glasiger strahistcin by Emmerling, 
and la rayonnante vitreuse by Brochant. : 
Besides this abominable deluge of names for the same sub- 
stance, the same name is sometimes applied by different 
writers to substances perfectly distinct. 
Where the chemical nomenclature cannot be applied, it would perhaps 
be a good rule to adopt the name given by the discoverer of the mineral. 
Our author’s plan is to adopt the chemical nomenclature for 
the speczes, in all cases where the composition is sufficiently 
known, with a familiar mineralogical name, and the synonyma 
of some of the most valuable modern writers. Subspecies and 
varieties are distinguished by mineralogical names already in 
use and well known. Earthy minerals of uncertain composition 
are generally named after Kirwan and Jameson, with such de- 
viations from their nomenclature as the progress of the science 
has called for. 
A brief enumeration of the substances of which minerals are 
composed closes this part. 
We have next a tabular view of our author’s arrangement. 
“* The divisions into species, and the nomenclature of the 
species, are perhaps as strictly chemical as the present state of 
mineralogical knowledge will permit.” The class of earthy 
compounds, which cannot be accurately divided into genera, 
have their species arranged after their composition, those most 
alike being collected into the same group. No ingredient, not 
amounting in an apparently pure specimen to at least five per 
cent., is considered essential; and others, “ in greater propor- 
tion, in obviously impure specimens, have been rejected as 
accidental.’ This is rather a loose method of determining 
whether an ingredient be essential to the composition of a mi- 
neral or not. The weights of the absolute quantities of the 
several substances, given by the analysis, should rather be 
compared. with those of their respective prime equivalents. 
This affords, at once, solid data for estimating the value of 
any ingredient, and the probable accuracy of the analysis. 
The tabular view cccupies eighteen pages: we can only give © 
a very slight outline of it. 
The substances are divided into four classes. The first class 
comprehends substances not metallic, composed, entirely or in 
part, of an acid. It contains four orders. Order 1.—Acrds 
not combined. The base of the acid determines the genus. 
Order 2.—Alkaline Salts. The alkali determines the genus. 
Order 3.—Earihy Salts. The earth determines the genus. 
Order 4.—Salts, with an alkaline and earthy base. 
