Petrifactions.’ MINER 
the ilrata immediately repofing on, or following, tra&s of 
granite, gneifs, and the other rocks, in which extraneous 
foflils are never imbedded. Strata containing the remains 
of filh and marine fheils. See. mixed fometimes with the 
parts of amphibious animals and plants, or thofe in 
which vegetables only occur, generally fucceed, or reft on, 
the trafts in which the exuviae of vermes alone are found. 
The remains of land-animals, particularly of the clafs 
mammalia, rarely occur in regular Ilrata. Animal reli- 
quite, particularly the marine, are moll common in cal¬ 
careous ftrata ; whereas vegetable reliquiae frequently oc¬ 
cupy argillaceous beds, efpeciaily thole productive of coal. 
The phenomena peculiar to petrifaClions are as follows. 
PetrifaClions are generally confined to mountains, or other 
elevated fituations, where the more ancient of the fecon- 
dary ftrata are prefented to our view ; they are ufually 
incorporated in the earths and ftones, of which thefe 
ftrata confift, forming, as it were, a part in the original 
fabric of the globe ; no particular petrifaClion is confined 
wholly to one kind or fpecies of ftones; the fubftance, 
which forms the petrifaClion, is frequently of the fame 
nature as the furrounding rock; when it differs, it is 
found to confift of mineral matter, with a finer texture or 
grain than that of the matrix. A petrifaClion often con- 
fills of feveral diftinCl minerals; thus chalk and flint often 
form l’eparate parts of an echinite; and in Derbylhire, chert, 
calcareous fpar, bitumen, and quartz, are frequently in¬ 
corporated together in the fame lhell. 
The common conftituent fubftances of petrifaClions are 
earths and Hones of the calcareous, argillaceous, or fili- 
ceous, clafs. Animal petrifaClions are lefs common, in 
proportion to the degree of locomotive power which the 
originals pofl'elfed. Shells and zoophytes abound in pe¬ 
trifactions ; filh and infeCts without wings are more rare. 
The petrified remains of mammalia are Hill lefs frequent; 
and winged iufeCts and birds have perhaps never been 
found in this Hate. 
The vegetable petrifaClions moll common are fuch as 
bear the form of plants growing in moift and boggy 
grounds. The petrifaClions hitherto recognized, how¬ 
ever, as bearing the forms of plants or animals known to 
exift at prefent, are very few, compared with thofe the 
living fpecies of which have not been difeovered. 
A petrifaction feldom, if ever, exhibits a complete 
change, or fubftitution of mineral for organic matter j 
more or lefs of the original animal or vegetable fubftance 
being generally prefent, and difcoverable either in the ex¬ 
ternal or internal parts of the foflil. In petrified fheils 
and corals, the original calcareous matter is frequently 
feen covering the l'urface, or remaining in finall portions 
in the internal parts ; and is readily diftinguilhed, although 
the fubftituted mineral, forming the principal portion of 
the foflil, be alfo calcareous. 
The petrifying procefs is carried on, in fome waters, at 
this day, of which we have a ftriking inftance at Matlock ; 
but it appears to be confined to the formation of petri¬ 
fied wood, or wood-llone. PetrifaClions rarely exift in 
veins. • 
The phenomena peculiar to the eonfervuta are as fol¬ 
low : they are for the molt part found in low or flat 
traCls, where the ftrata are evidently of modern forma¬ 
tion. They are alio found in the caves and fiflures which 
pervade the more ancient mountain-ftrata, but are rarely 
incorporated in the Hone, or other fubftance of which 
fuch ftrata confift ; they occur alfo in the beds of rivers, 
and in moll fituations where mineral or other matter is 
daily accumulating ; they are found in all Hates, between 
that in which aCtual decay takes place, and that in which 
farther decay is prevented, either by a new combination 
in the remaining principles, by an impregnation with 
mineral particles, or by fome other natural procefs inci¬ 
dent to thefe bodies. The animal confervata moll com¬ 
mon are fuch remains as are moll rare in the petrified Hate, 
filch as the bones of mammalia and filh, and fliells of the 
fame genera as thofe found in the neighbouring leas. 
A L O G Y. Petrifactions/ 510 
The moll common vegetable confervata are wood, and 
other parts of trees ; they are more frequently referable 
to plants and animals now exifting than the petrifafta, 
and they are not uncommon in mineral veins. 
The origin of extraneous foflils is fliown by thfe atten¬ 
dant phenomena. 1 he confervata cannot be laid to origi¬ 
nate from, fince they really are the remains of, plants and 
animals, introduced, by different procefies of nature, into 
the mineral kingdom : but petrfutta owe their form to 
organized bodies ; they derive their fubftance generally 
from minerals. 
Mr. Martin, in a note, p. 3 6, fays, “ It perhaps may 
be doubted, if any depofition of organic bodies has ever 
yet occurred, unequivocally demonllrative of a general 
flood. _ The lhells found in Peru, on a mountain confider- 
ably higher than any affording fimilar remains in Europe, 
appear to have been perfeCl petrifaClions, included in the 
fubftance of the Hone of which the mountain coniifts ; of 
courfe, they prove the fubmarine formation of the rock 
in queftion, but not that its contents have been elevated 
to their prelent fituation by the deluge. Even loofe or 
tinconfolidated depofits of marine remains, fometimes 
found, according to Pallas, in the more external fiflures 
and veins of lofty primary rocks, in which extraneous 
foflils do not occur as integrant parts, are no certain proof 
of this event. It is highly probable, that fecondary ftrata 
have originally covered many elevated trails, where there 
is at prefent no appearance of fuch formation ; and that 
extraneous foflils, formerly imbedded in thele fecondary 
ftrata, will remain in a very complete Hate of preferva- 
tion, long after their original matrix has been deftroyed, 
is indeed a fait fufficiently illullrated by the loofe reli- 
quia fo abundant in the common foil of fome countries, 
and which have been liberated undoubtedly by the wafte 
and decay of their native rock. When, however, the re¬ 
mains of marine and of land animals occur together, in 
fuperficial accumulations, they certainly exhibit a lels- 
ambiguou* evidence of the deluge : yet not altogether a 
decifive pne, except both kinds of reliquiaare found in a 
fimilar Hate of prefervation. If, on the contrary, the 
fliells are petrified, and the bones are in nearly a recent or 
unmineralized condition, it is obvious that they were not 
originally introduced into the foflil kingdom at the lame 
period ; and hence the fupport which the prefence of ma¬ 
rine objeCls gives to the conclufion, that fuch depofits are 
truly diluvian, is done away with.'’ Mr. Martin adds, 
“ It mull not be inferred, that we wifli to effhblifii a dis¬ 
belief of the general deluge. The exiftence of that event 
is confirmed by authority far above the evidence of geolo¬ 
gical facts. But, in the prefent ftudy, it is neceflary to 
guard again ft the too common error of aferibing effects to 
caufes inadequate to their produ&ion.” 
Mr. Parkinfon’s conclufions are, that it appears obvious, 
from what has actually been difeovered, that a confiderable 
number of fpecies, kinds, and perhaps orders, of animal, 
vegetable, and mineral, materials, have been loll for ages ; 
and conlequently that the general Hate and inhabitants of 
the earth have undergone fome very remote and very con¬ 
fiderable change ; and it mult be equally obvious, that 
fuch change mull have been produced by fome fuch event 
as the deluge deferibed in the Old Teftament; the book 
of nature thus bearing ample evidence to the truth of the 
book of revelation. Nothing, he adds, is clearer than, 
judging from the general nature of the foflil materials of 
the antediluvian world which have reached us, or at lead: 
are known to have reached us, that the poft-diluvian 
world has a very high comparative advantage, is aClually 
richer, and to a confiderable extent, in yaiuable produc¬ 
tions, and is much more fitted for the neceffaries, and 
even comforts and luxuries, of civilized life. Hence, in¬ 
dependently of the accomplifhment of any other im¬ 
portant purpofe, by the revolution of a former world, one 
grand objeft appears to have been attained, viz. luch ail 
arrangement of the teeming ruin, as produced the rege¬ 
neration of a world llored, in its deepelt recedes, wTth 
* fubftance* 
