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times another, to indicate the interior difference, that is to
say, the composition ; in the second place, because each ex-
terior character sometimes arises from an essential difference,
at other times only from an accidental variety. The systems
of those who have inclined to arrange minerals by their ex-
ternal characters, may already furnish proof of the inconve-
niences of this method, because we there see minerals
brought together which are essentially different j and that
those of the same kind are separated by reason of some acci-
dental variety. Botanists and Zoologists have this advantage,
that in the objects of those sciences they find the conformities
of bodies by their exterior ; and that while they endeavour
to class them, according to the aggregation of their external
parts (or organs), they describe also their external characters,
and in some measure accomplish these two objects at the
same time. The labour of mineralogists is quite different ;
they must determine at once the composition of minerals by
their appearances under chemical operations, or otherwise
leave it to be determined by the chemists, and consequently
class them accordingly. They ought, on the other hand, to
seek after their exterior characters, in order to complete the
description from them.

" I shall also remark, in the first place, that mineralogists
hitherto seem to me to have been too much attached to the



INTRODUCTION. XHl

retention, in their systems, of the four gradual divisions of
the logicians, into classes, orders, genera, and species; and
that, to a certain degree, they thereby do violence to nature,
I, nevertheless, believe that in this respect we may determine
something certain ; that is to say, how many degrees there
are in the division of minerals according to their constituent
parts : but as this is not the place to enlarge on this subject,
I shall reserve it for another occasion, since, in regard to the
subdivisions, it is always well to preserve those once intro-
duced.

fc I shall observe, in the second place, that mineralogists
are little agreed, and are even undecided, with regard to
what they call the species : if we would take this word in a
determined sense, in general, all minerals that essentially
differ from one another in the relations of their composition
form different species 5 and all those that essentially assimilate
in these relations, should be considered as forming one sole
species. Moreover, all the separate pieces of one species are
individuals*, to which we substitute the word species, because
it is impossible to have at the same time the entire species
which comprises all the mineral individuals which may be
found buried under the earth, or upon its surface. In short,
all the minerals by which one species passes into another,
and which accidentally differ in one or other of its charac-
ters, are varieties"^

The division into Genus and Species seems, as Werner here Species of
justly observes, to have been first conceived by the writers lo g" lciaus -

* Tliis word is a further proof of the absurdity of the classification ; for a
plant or an animal may be an individual, but a mineral may always be divided
md infinitum.

+ Werner, Traite* des Caraeteres Exterieurs des Fossiles, trad, de Madame
Picardet, Paris, 1790, 8vo. p. 9 18.

The German terms used by Werner (see Prindpes de Mineralogie, par
Berthout et Struve, Paris an 3,) are Geschlechter for Genus ; Gattungen for
Species; Arten for Sul-spedes. The first (see Schwan) means genus, species,
race, nay genders, nation. The second, sort, manner, species of animals.
The third, sort, species, race,, nature, complexion, air, manner, custom,
fashion.






XIV INTRODUCTION.

on rhetoric and logic. The great Milton, in his Latin
treatise on logic*, has discussed this subject, chiefly on the
authority of Aristotle and Cicero : his examples are only
accidentally from living beings ; and he even appears embar-
rassed to distinguish between the species and individuals j for
he argues that, as form is admitted by Aristotle as a discri-
mination of the species, and every man differs in form from
another, so every man must form a distinct species. He
adds, that the lawyers allow man to be a genus, while indi-
viduals constitute the species j but he observes, that Ovid
divides the genus ANIMAL intone species: Stars, Birds, Beasts,
Fishes, and Men. So Cicero divides virtue into four species:
Prudence, Justice, Fortitude, and Temperance. The pe-
dantry of this great poet is truly risible -, but thus it was
when logic was the art of talking nonsense according to a
fixed method. Yet it is from logic, as Werner and the other
German mineralogists allow, that the imaginary distinctions
of genub and species were admitted into mineralogy !

Dolomieu being sensible that the whole process depended
\ipon ascertaining the species, which if once admitted, the
genera, &c. would follow of course, has employed much
metaphysical reasoning in his usual prolix, confused, and
digressive style, to ascertain an imaginary species in mine-
ralogy. He ought to have begun by informing his readers,
that he was only discussing the word species, as used in
modern natural history, where, in that of animated nature, it
has become a useful distinction. But the ancient and clas-
sical senses may be learned from the commonest dictionariesf.

London, 167-2, 12mo. cap. 27.

f As for example that of Ainsworth. " SPECIES, ei. f. (a SPECIO.) (l.) A
form, figure, fashion, or shape. (2.) A sight, or object presented to the sight.
(3.) A likeness, or representation. (4.) An outward show, or appearance.
(5.) Colour or pretence. (6.) A vision or sight, a spectre. (7.) An image,
picture, or statue. (8.) An example, a specimen or instance. (9.) The quality
or nature of a thing, (10.) Also a particular sort, a kind of things under a
general head, (ll.) Sight or view. (12.) All kinds of spice, a drug. (13.)
Corn cr fruit. (14.) A piece of money. (1 5.) A garment, or apparel. (16.)



INTRODUCTION. XV

It is indeed not a little remarkable that, among the nume- Classical
rous senses in which the word species is used by the Roman
classics, there is little appearance of its modern sense in natural
history. Nay, even in the modern languages, all its deriva-
tions and collaterals may be equally said to be foreign to that
acceptation j as for example in the English, special, specially,
specialty, specific, specifically, specificate, specification, specify ,
specimen, specious, speciously. It therefore chiefly belongs, with
the greater part of the Linnean language, to a modern latinity
so barbarous, as even to confound genders and cases, and
many others of the commonest rules of grammar.

But to return to its use in modern mineralogy. In his
able criticism on Haiiy's Tableau Comparatif, the last fruit of
the researches of that eminent crystallogist, Lametherie has
shown that the supposed species can be ascertained by no means
but that of chemical analysis ; and that the doctrine of the
integrant molecule has been abandoned by Haiiy himself*.

Any sort of meat. (17.) A controversy. (l.) Species et figura humana, Cic,
pro T. Rose. 22. Specie lepida mulier, Plant, Rud. 2, 4, 2. Promissa barba
et capilli efferaverant speciem oris, Liv. 2, 23. (2.) Non tulit hanc speciem
furiata mente Choroebus, Firg. En. 2, 407. (3.) Speciem ac formara similem
gerit ejus imago, Lucr. 4, 49. (4.) Moveri falsa visione, et specie doloris,
Cic. Tusc. 2, 18. Prseter speciem alienae fungendae vicis suas opes firmavit,
Liv. (5.) X Securitas specie blanda, reipsa repudianda, Cic. de Amic.13.
(6.) Non priu.s hostem destitit insequi, quam species barbarae mulieris humani
amplior, victorem tendere ultra sermone Latir.o prohibuisset, Suet. Claud. 1.
Sibi quoque eandem speciem aliquot jam noctibus observari retulit. Id. ib. 37.
Species Homeri, Lucr. 1, 125. (7.) Ex acre species vetus, ap. Cic. Div. l,
12. Est aurigce species Vertumnus, Prop. 4, 2, 35. (8.) Hanc speciem
libertatis esse, si omnibus, quod quisque vellet, legibus experiri liceret. Ncp.
Timol. sulfin. (9.) Liv. 35, 49. (10.) X Cum genere idem sit, fit aliud, quod
quadam parte et specie differat, Cic. de Inv. 1,27. ^ In universum, Tac.
Germ. 5. (H) Luna potest majus lumen convertere nobis. Ad speciem,
Luc. 5, 7O4. (12.) Curabis ut specierum vis omne corpus inficiat, Pall. Octal:
tit. 14. (13.) Arced. (14.) Litt. ex Macr. (15.) Capit. (16.) Lampr.
(17.) Dig."

* L'analyse ne prouve que le fer chromate est une espece, que parce qu'elle
y troure constamment les mfimes principes. Done il n'y a que 1'analyse qui
determine les esp^ces. Done touts substance, cdstallisee ou non,






As it is therefore granted on all hands, that chemistry alone
can decide what is called the species, and that it depends chiefly
on the MODE OF COMBINATION, is it not more logical and
philosophical to adopt the only term which can express its
real nature ?

It is clear that Haiiy has abandoned his doctrine of species,
in which he had followed Dolomieu, who assumed the mole-
cule integrante of Del isle as the basis of a species*. Dolomieu
closes his elaborate essay on the subject with the following
strange definition of a species, in fact a mere ens rationis in
mineralogy.

Dolomien's " The mineralogic species is a being distinct from all
ies ' others by a particular constitution, and which receives from
that constitution every thing which should characterise it.
This being exists in the integrant molecule, is physically re-
presented by the homogenous masses which have been sub-
mitted to the laws of regular aggregation, and it holds under
its dependence all the beings which have a similar constitu-
tion, even when faults of conformation set them at a distance
from the physical representation of the species, or when
superfluities and contaminations make it wear a foreign
livery." A very curious and original specimen of a defini-
tion !

Though Werner repeatedly allows that all mineralogical
arrangements must depend upon chemistry, as they can only
be formed on the quality, and quantity, and mode of combi-
nation of the constituent parts ; yet, with a not illaudable
predilection in favour of natural characters, he uses them
chiefly to decide the species j while the species is in fact
the most important and the most dependent upon chemical

retire constamment Ies me'mes princlpes, est une espece. II n'est pas necessaire
de savoir si elle a une molecule. Mais Panalyse seule est insuffisante, il faut
encore avoir egarcl aux caracteres exterieurs, et aux proprie'te's physiques j commo-
pour le spatte calcaire et Parragouite, le ruthil et 1'oisanite. Journ. de PA.
Juillet, 1809.

* See Tableau, p. ii. " J'ai prl&rl Vindication de la forme primitive a celle
de la molecule integrante" &c.



INTRODUCTION.

aid*. Hence have arisen the chief errors in his system, ably
exposed by Chenevix, who has shown that the different
species of Werner are often vague and indeterminate 5 and
the order of his arrangement not seldom capricious and
imaginary, and far from being founded on his own principle
of chemical composition. The calcareous spars are united
under several groups, according to the acid which predomi-
nates. Those he has marked A, B, C, D, are truly German
distinctions. Dr. Thomson has justly observed, that by his
use of groups and families, Werner is struggling against his
own system.

But the mode admitted in the place of the species, obviates
these difficulties. It presents a real chief distinction between
the species, that founded on chemical analysis, as it. refers to
the mode of combination, the ruling principle in the difference
between one mineral and another, considered even in the
most abstracted point of view, and with regard to the purest
substances, as crystals, gems, &c. ; as even a variation in the
water of crystallisation sometimes distinguishes one mode
from another. But though what are admitted as distinct
modes, will perhaps always be found to differ in chemical
analysis j yet as the science does not admit of too much pre-
cision, while the substances themselves are always variable,
as partaking of a mutual nature, and only portions of that
vast mixture the shell of the globe ; the mode may also more
laxly be understood to include some modifications of external
characters, under what is called aggregation in particular.
Thus the aggregated stones may become modes, as well as
the combined. But in passing to the Structure and Aspect,
the chemical characteristics may in general be considered as
abandoned, or exchanged for the physical or external.

This unavoidable uncertainty has been well illustrated by
the greatest of petralogists.

* Bergman, the father of the system, derives the species from chemistry.
See also Brcchant, i. 47. Jameson, i. xxv.

VOL. I. b



xviii INTRODUCTION.

obs a erv S atio S " OnC cannot too often repeat that there must be found in
the mineral world, and that in effect in it are found, all the
mixtures in all imaginable proportions, from which proceed
an infinite number of mixed and undetermined kinds.

" If in the kingdom of organised beings, where the spe-
cific forms are determined by the seeds, it is often difficult to
mark the limits of the species ; how much more so to ascer-
tain them in one where only the force of cohesion unites the
elements, whatever be their nature, and in whatever propor-
tion chance collects them.

<( It is for this reason that in this work I have avoided
giving names to the stones I have written of, when I have
not been able to ascertain them by decided marks, which
could fix their place in the known system of the nomen-
clature.

" Those who collect, and the nomenclators properly so
called, do not like these doubtful sorts, which it is too diffi-
cult to arrange under the known genera. They neglect or
even reject them entirely, because they appear to reproach
the imperfection of their systems. For this reason one sees,
in the greatest number of cabinets, only the sorts whose cha-
racters are decidedly known. There nothing stops you, all
is conformable to received systems, and all have fixed names.
But when nature is studied by herself, when one proposes,
instead of finding cabinet specimens, to study minutely all
the productions of the mineral kingdom, and is at the same
time jealous of a certain degree of precision, one finds at
every step individuals which it may be said to be impossible to
arrange under known denominations. One may then mark
the bounds j one may determine how far each individual ap-
proaches to, or recedes from, such and such a species ; but
one cannot positively affirm the name of the one or other of
these species*"*

* Saussure, ii. 606.

I



INTRODUCTION.



2. Order of the distinctive Characters.

The present work may be said to have passed through
several editions, before its public appearance ; and the por-
tions newly modified, or finally rejected, with the detached
discussions, composed in order to consolidate the progress
and universal consistency of the plan, would form a moderate
volume. These precautions became necessary, as upon an
unknown coast the discoverer employs boats to sound the
bottom, before the ship can advance with safety. Among
numerous difficulties, which will be perceived in proportion
to the learning of the reader, the arrangement of the cha-
racters, and the choice of one or two of the new terms, were
not the least. They now stand as follow: Texture, Hard- Order
ness, Fracture, Fragments, Weight, Lustre,, Transparency -, P r P se
to which the colour is sometimes added, though the most
vague and insignificant of all the characteristics.

Murray, in his excellent System of Chemistry, has justly Objections to
observed that it is difficult to attach precise ideas to arbitrary
numbers. Every reader must have observed, that he passes
without, reflection the ciphers 1, 2, 3., &c. when applied to
Hardness, Specific Gravity, Lustre, or Transparency. It
therefore seemed more advantageous to employ terms derived
from the substances themselves, which, though only relative
and recollective, yet convey ideas more clear, and, so to
speak, more tangible than barren ciphers. In this, and other
instances, the reader not conversant with modern mineralogy



may perhaps be surprised at the neology: but he must be . Neology
informed that the science itself is entirely new; and that mdls P ensable '
there is no recent mineralogical work which does not abound
with new terms, not to be found in any dictionary, but which
are indispensably necessary, in order to delineate substances
and qualities which did not before fall within the range of
human intellect or language. The names which have been
added to botany and zoology, within half a century, might be

b2



<,



xx



Nexr terms.






Hardness.



Weight.






ODUCTION.



:



INTRODUCTIO






counted by hundreds ; and in the progress of mineralogy, a
similar neology cannot be avoided. While some recent
authors of mineralogy pollute the classical language of our
fathers with an inundation of barbarous German words, de-
rived from the vulgar dialects of illiterate miners, who of
course first observed the distinctions between mineral bodies >
it became the more an object of ambition to treat this diffi-
cult subject with such a degree of classical purity, as not to
disgust the eye of taste, contemn the discussions of gram-
mar, or vitiate the eternal tenor of our language.

The new terms chiefly required, were to designate the
degrees of hardness and weight, which had been indicated by
ciphers, even by authors who used epithets to express the
other characters. As Chalk, Gypsum, Marble, Basalt, Fel-
spar, Rock Crystal, and Corundon, form various stages of
hardness, at the distance of 200 or more in the common
tables, they have been chosen to express the relative hardness
of other substances, by the following terms : Cretic, Gypsic,
Marmoric, Basaltic^ Felsparic, Crystalic, Corundic. In order
to diversify the form of the epithets, the weight has been
designated by another Latin adjective termination, that in
osus, which some grammarians affirm generally to denote
weight or labour, as labor iosus, ponder osus, operosus, &c. and
the last word has even been admitted into classical English
in the form operose. As Pumice, Coal, Granite, Siderite,
and Barytes, form a scale of gradations in weight, they are
here selected to denote that quality, as being Pumicose, Car-
bonose, Granitose, Siderose, Barytose.

But the characters themselves, and their arrangement,
require further explanations. The Texture and Hardness
occupy the first place, because adepts generally examine them
first, by means of the lens and knife. Dr. Townson has
erved that these instruments should always be in the
cet of a mineralogist. {f With the latter, after a little
practice, he will be able readily to find the hardness of most
fossils j and the former will furnish him with very accurate




V



TRODUCTION. XXI

knowledge of their texture, and be of particular use in
many of his geological speculations on their formations."*

This skilful author has arranged his characters in the fol-
lowing order : Texture, Fracture, Lustre, Hardness, Fra-
gility, Transparency, Fragments, Colour. It: is hoped the
present arrangement will be found more justly progressive

and connected. But after having advanced several coerent Townson's

difficulties.

arguments against Werner s arrangement, m his tenth chap-
ter, which treats of Classification, Description, and Investi-
gation, he strangely introduces the following remark in his
ninth chapter, on the Exterior Characters of Minerals, which
hence appears to have been written after the tenth. " Though
I have made some objections, in my tenth chapter, to the
order of the characters in the descriptions, disapproving of
their beginning by their least characteristic qualities, as co-
lour and accidental shapes -, yet I perceive, were I to throw
these further backward, other inconveniences would be the
consequence. The characters belonging to each of the three
different states of cohesion, as solid, friable, and fluid, are
placed under their respective heads j but the colours, being
common to all the three, are placed first." This is certainly
a specimen of careless composition. The supposed inconve-
niences ought to have been indicated, if they did not consist
in the labour, certainly not small, of altering or rewriting
a system already composed, in order to render it coherent and
uniform. But the forcible arguments, in his tenth chapter,
remain unconfutedj and the arrangement of Werner's cha-
racters haslet with other able opponents. His extreme Werner's
attachment to the distinction of colours, from which he has incon & ruities -
even deduced many improper, not to say absurd, appellations
of mineral substances, has led him to place this vague cha-
racteristic in the first rank. The incongruity of the concate-
nation has been justly ridiculed in other respects. From the
*,ustre he passes to the Fracture, and from the Fracture to
the Transparency j from the Coldness to the Weight, and

ttp

* Philosophy of Mineralogy, London, 1793, 8vo. p, 187*



i



XXll INTRODUCTION.

from the Weight to the Smell. It would certainly have been
more natural and rational to have joined the Lustre with the
Colour, and the Weight with the Hardness. His idea of the
successive use of the senses, in the examination of any mine"*
ral, is quite imaginary ; as before an examination with a lens,
it may be weighed in the hand, or its hardness tried with a
knife, &c. -, and it would be ridiculous to build a science
upon simple exertions of the will. Independently of this new
kind of pedantry, derived from German metaphysics, it is
not the consideration what senses are first impressed, that
should regulate the succession of characteristics ; but, on the
contrary, their own intrinsic importance. Hence the TEX-
TURE is here placed in the first rank, though totally omitted
by Werner, or confounded with the fracture, with which
indeed it is intimately allied : but two other celebrated mi-
neralogists, Wiedenman and Estner, have justly introduced
the texture as a characteristic of the most radical importance.
In many cases it may be judged by the eye, but in most
requires a lens. The hardness, which follows, may be tried
by the knife or file instruments indispensable to the mine-
ralogist. The weight may, after some experience, be esti-
mated by the hand; but some of .the disciples of Werner
have confounded this external character with the specific
gravity, which belongs to the chemical class of characters.

Mr Kirwan has justly observed the inaccuracy of Werner
and his disciples, who have confounded the texture with the
fracture. The most minute account of the former, is that
by Dr. Townson above mentioned.

Townsonon " The Texture, Textura,

the texture.

" Is the internal structure or disposition of the matter of
which a mineral is composed*.

* " Mr. Werner says nothing on the texture of minerals ; but, under th
article of fracture, gives many characters which belong not to the fracture but to
the texture ; so that the characters of textute and fracture, though very different,
are united under one head and confounded together. But in the works of




INTRODUCTION.



("Without any distinguishable parts, or the ap-
< pearance of being composed of smaller
(. parts. Examples, Chalcedony, Flint, &c.

\ When composed of very minute, almost invi-
") sible, rough parts, as clay, marl, &c.

j When composed of small shapeless grains, as
granulated quartz, sandstone, &c.



pact

Compact a
Dicht
Earthy
Terrea
Erdig
Granular
Granulata
Kornig

Globuliform f When composed of small spherical bodies, as
Globuliformis \ , the pisolithus and oolithus.
Fibrous ( When composed of fibres. Examples, Fibrous

Fibrosa < gypsum and amianthus.

Faserig ( The fibres may be

Fine
Coarse

Long

Short

Straight

Crooked



Temdbus


Parallel


Parallels


Crassis
Longis
Brevibus


Divergent
Stellated
Fasciculated


Divergentibus
Stellatis
Fasciculatis


Rectis


Decussated


Decussatis.



Curvatis

When composed of long, narrow, flattish la-
mellae. This differs from the fibrous by the
parts being broader. Examples, grey anti-
mony, manganese, zeolite, actynolite, &c.
This admits of the same variations as the
preceding.

When composed of smooth continued leaves or
plates, covering one another. Example, as
the spars. They may be



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