MINERALOGY. 
440 , 
containing the Hones, i-s divided into three orders; the 
firft, hard ftones ; the fecond, magnefian ; and the third, ar¬ 
gillaceous. The fourth clafs contains the combuftible 
fubftances, which are divided into two orders ; firft com¬ 
pound, and fecond fimple, combuftibles. The fifth clafs 
includes the metals, which are divided into two orders ; 
firft the brittle, and fecond the duCtile, metals. The 
treatife of Brongniart, notwithftanding fome peculiari¬ 
ties in the clafiification which are not quite familiar to 
us, will be found one of the raoft ufeful that has hitherto 
appeared, not only on account of the accuracy of the de- 
fcriptions, which are divefted of every kind of redundancy, 
but alfo on account of the interefting geological difcuftions 
which are introduced, as well as numerous and important 
practical details in metallurgy and other ufeful arts. 
20. Kidd’s Outlines of Mineralogy; Oxford, 1809. 
This fyftem is formed upon that of Kirwan, (or Werner,) 
with fome judicious alterations, and including the new 
difcoveries. 
ji. Mr. Richard Chenevix publifhed, in the year 1808, 
in the Annales de Chimie, “ Obfervations on Mineralo- 
gical Syllems.” His chief defign was to impugn that 
which has been framed by Werner, and to advocate the 
caufe of cryftallography as expounded by Haiiy. In juf- 
tice to the learned and celebrated profeffor of Freyberg, 
it behoves us to remark, that he neither publithed nor 
completed any fyftematical arrangement of mineral fub- 
ftances, but that he merely Iketched the principles of a 
plan which his pupils, w ith various fuccefs, have attempt¬ 
ed to realize ; and that the faults of the fcholar may often 
not be attributable to the mafter. Yet the prefent writer 
admits that, by the ditlinCtions and clafiification of the 
external characters, “ a great advance has been made, 
which, if it has not led dire&ly to the objeCt in view, 
{hows at lead the difficulty of the talk ; that, during the 
refidence of eighteen months at Freyberg, he had daily 
occafion to admire the precifion and accuracy with u'hich 
the learned profeffor recognifed minerals at firft fight; 
that the fyftem of external characters by Werner, in the 
form in which it is made know n to us by the books that 
treat of it, is infinitely fuperior to any thing of the kind 
that ever appeared before it; and that it rnuft he of 
the greateft utility to the miner.” We might add that 
every individual, who has paid the flighted: attention to 
the ftudy of mineralogy, muft be convinced of the great 
difficulty of difcriminating the unorganized portions of 
matter by permanent fpecific characters. Some of the 
molt profound naturalifts, who have appeared in modern 
times, have even hinted their doubts of the real exiftence 
of fpecies in the vegetable and animal kingdom ; becaule 
the multiplied difcoveries in thefe departments feem only 
to approximate former diftinftions by intermediate fliades, 
and to prove that marked lines of feparation are unknown 
in nature. However this may be, it is at all events cer¬ 
tain that mineral fubftances are much lefs fufceptible of 
difiinft definition than plants and animals ; and that he 
who enables us to recognize them, by their external cha¬ 
racters and afpe&s, performs a fervice of infinite conve¬ 
nience and benefit to mankind. 
The fyftem of Haiiy, again, which is here extolled (in 
ourapprehenfion) above its real merits, profeffes to found 
its diftinCtions and diviftons on the integrant molecule, 
combined with the chemical compofition. The author 
of thefe obfervations Hates the ground of this principle 
.of arrangement, and unfolds the principle itfelf in a very 
luminous and impreflive manner; but the queftion ftill 
occurs, Will the ftudent of cryftalline forms, or of exter¬ 
nal characters, firft and moft readily be enabled to difcri- 
minate the foil'll matters with which we are lurrounded ? 
'I he former is well aware that the deteClion of the inte¬ 
grant molecule is not very eafily nor very fpeedily accom- 
piiffied; and that a knowledge of the forms, deducible 
irom the primitive or original cryftal, prefuppofes a cer¬ 
tain degree of familiarity with geometry. The chemical 
analyfis, too, of the moft common ftohe, is an operation of 
very confiderable delicacy; requiring not only a fuitable 
apparatus of inftruments, tefts, and re-agents, but time, 
patience, and Ikilful manipulation. Few individuals, in 
ffiort, can command leifure and fortune, or poffefs op¬ 
portunity and ability, for fubjeCling every mineral fpeci- 
men which prefents itfelf to chemical trials, on the ifiue 
of which he can place any reliance. In many inftances, 
indeed, the refults of analyfes, apparently conducted with 
the utmoft accuracy, are deceptive or difcordant, lo that 
they cannot with propriety be adopted as the liable bales 
of permanent arrangements. In fome cafes, there is even 
realon to prefume that new combinations are formed 
during the procefs. Objections might alio be urged againll 
the uniformly geometrical accuracy of the integrant mole¬ 
cules, or leaft conceivable particles of matter; for De la 
Metherie, and others, have proved that the forms attri¬ 
buted to the molecules are often hypothetical; the mea- 
fure of angles by the gonyometer being, on fome occafions, 
incident to an error of half a degree, or upwards ; and 
different calculators report different meafurements. Yet 
on the rigid exaClnefs of the forms of the molecule de¬ 
pend all the laws of decrement which have been affigned 
to thefe forms. Belides, as many fpecies do either not 
exift in a cryftallized form, or have not hitherto been 
found in that Hate, they are in courfe excluded from the 
method, and thrown into a voluminous appendix. Grant¬ 
ing, therefore, that this method is perfectly correCt and 
purely fcientific as far as it goes, it is ftill only a partial 
record of the kinds of fubftances which compofe the mi¬ 
neral kingdom. 
While Mr. Chenevix infills on the liability of M. Haiiy’s 
arrangements, he admits that this celebrated mineralogift 
has adopted very material changes fince its publication ; 
but thefe changes, he informs us, were foreleen and pre¬ 
dicted by the author. Whether Werner, alfo, forefaw and 
predicted the alterations to which he has at different times 
had recourfe, we lhall not pretend to determine; but we 
much miftake if many and important changes do not 
await both the fyftems in queftion ; for the Icience of mi¬ 
neralogy, it muft be confeiied, is ftill in its cradle; and it 
may be the envied lot of fome individual to point out 
more obvious and lefs fallible fources of diftinguilhing 
its contents than any that have been hitherto propofed. 
In the mean time, w'herefore ffiould the mealurer of primi¬ 
tive forms, real or imaginary, deride the recorder of ex¬ 
ternal characters ? Their joint labours, even when aided 
by thole of the chemill, will not, in all cafes, fuffice to in¬ 
dicate “ the truth, the whole truth, and nothing; but the 
truth.” 
44. Dr. Clarke’s Methodical Diftribution ; folio, 1811. 
This fyftem is more purely chemical than any which have 
preceded it. The character of the claffes, of -which there 
are four, viz. Earths, Metals, Combuftibles, and Alkalies, 
is derived from the predominating elementary principles. 
The firft clafs, the Earths, includes two orders, which are 
characterized by the property of the earth in combination 
with an acid, or without an acid. Each earth conftitutes 
a genus ; the fpecies are formed according to the peculiar 
combinations of minerals ; and the varieties are deiignated 
by their trivial names. 
Some perlons are of opinion, that, in the prefent ftate 
of mineralogical Icience, it is expedient that there fitould 
be two diftinCl fyftems ; the one which fitould arrange mi¬ 
nerals according to the appearances and properties by 
which they may be the moft eafily dillinguiflted ; the other, 
which ffiould be ftriClly fcientific, in which minerals ffiail 
be arranged according to their conilituent parts, and the 
proportions in which they combine ; the latter fyftem muft 
be dependent on the progrefs of chemiftry for the ftate of 
perfection it may attain. Both thefe methods of arrange-, 
ment have recently been adopted ; the firft by Mr. Arthur 
Aikin, in his Manual of Mineralogy; the iecond by the 
celebrated Swedifli chemill, Berzelius, in a work entitled 
An 
