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some future day the design of giving a more ample explanation of those sciences, as .
supplement to my wo r k b^gun about twenty years ago. I shall
here likewise inform my reader, that, knov^ing the extreme, and I may add the almost
insurmountable difficulties, experienced by those who hitherto have endeavoured to
give a genera! theory of the earth, I am far from wishing to be understood as attempting
such an under taking, -being thoroughly convinced, as mentioned in a former work,
that it must be deemed impossible to proceed with certainty in this laborious and w.de
pursuit, and to explain the solution of that great problem, until a sufficient number of
facts and observations be collected on the subject, in order to draw some certain consequences
from them, to serve, as it were, for a basis ; and which, not being repugnant
judgement, shall agree with the curious and wonderful natural phenomena
with which our globe abom^ds. Nevertheless, as it is impossible to make any considerable
progress either in geology or lithology, without having previously formed
some notions on the origin and formation of mountains, I shall here subjoin some few
ideas relative to those subjects.
As to the origin of the primitive mountains, naturalists are at present mostly
agreed that their formation maybe attributed to an aggregate crystallisation of vitrlfiable
parts, such as quartz, feldspath or felspar, mica, schorl, &c. originally crystallised
in the menstruum, or ambient fluid, which at that time covered the globe to such an
extreme height as to snrpass the tops of the most elevated peaks of the Andes or Cordeleras,
in South America, as well as the primitive chain of the Alps, &c.
The above supposition, which seems highly probable, as every thing may be said f
evince the truth or certainty of it, is entirely due to tiie great progress lately made in
crystallography, by which nearly all the different and various forms or figures adopted
by the particular salts and crystals are at present determined or defined. From this
it results, that the granites, which are only a compound of small crystals, as before
mentioned, adopt, almost every-where, a polyedrous figure, the masses of which have, in
course of time, by their entassmens, or heaping one on the otiier, formed those stupendous
spiry peaks, called by the inhabitants of those countries pyramids, cones, and
aiguÜks, or needles, which constitute the primitive chain of the Alps, Andes*, i
other mountains of like magnitude.
• There is, howi
unknown in Üic Alp«.
in this chain, a numlicr of volcanocs of great height,-» circumstance hiiherlo wholly
107
Owing to the extreme irregularity which takes place in the structure of those moun-
. tains, and the confusion with which their constituent parts are united, added to their
position, and the singular arrangement of the metallic veins they contain, it is reasonable
to infer that their crystallisation may be considered as interrupted or retarded,—
or, in other words, that it had been effected at a time when the fluid in which it was
taking place (which kept in a state of dissolution and suspension every particle of that
crystallisation) was extremely agitated; and that besides, in that state of agitation, it
acquired a degree of heat from the subterraneous fires, which, to all appearance, seem
to have existed even at that epoch.
T o this argument, I grant, may be objected, that, as all the primitive matter which
forms the granites and porphjTy does not apparently contain any, or at least but a very
small portion of acids, their crystallisation cannot be so easily conceived: yet if we
observe that the felspar, zoolites, gemm®, as well as most of the vitriiiable stones, as
the schorls, silex, &c, which, in the first place, contain particles of siliceous earth j
i2d]y, calcareous matter, in a caustic state 5 3dly, magnesia, in a similar state; 4thly,
argiUaceous earth; and, 5thly, ferruginous matter; and that each of those earths are
soluble in water, it may be supposed that they have served as a dissolvent to each
other, and afterwards crystallised when circumstances were favourable to them,—i t being
now a received, and, I believe, a general opinion, that bodies, or substances, which are
in a dissolvent state, are capable of crystallisation (if not prevented by some cause), as
sulphur, metals, and even phosphorus: in fine, water, in a congealed state, is it not a
true pure crystallisation ? But if the above facts, added to many others, which might
be deemed tedious to enumerate, leave scarcely a doubt as to the manner in which the
formation of the primitive mountains has been effected, it does not still appear quite so
easy to prove that the secondary and tertiary ones owe theirs to a simiJar cause, though all
appearances tend to demonstrate that they do, which seems likewise to strengthen the
preceding conjcctures •, for supposing they owe their existence to an effect or operation
of pure and direct precipitations, as well as to the successive sediments of the sea,
why, may it not be asked, are there not some of the same kind continually forming at
the bottom of the ocean ?—a circumstance which we know not to be the case.
I t is true that there are naturalists who still attribute the formation of the major part
of the secondary and tertiary mountains to the reiterated operations of volcanic effects,—
subterraneous fires, as before noticed, being supposed at that time to have been very