MINERALS. 
7 
as there are fpecies of animals and vegetables; The intelligent 
inveitigator will not therefore ifraitcii the limits of an ufeful fci- 
ence, by difregardiag the ancient inhabitants of the globe, though 
unknown to modern naturalills. The modes of petrifadfion are 
principally fourfold ; Folhls, fubltances reltored, fubltances im- 
prelfed, and lublfaticts tranfublfantiated ; and are more frequent in 
Marble, Flint, Schill, Sand Hone, Rock, and Qyiartz. 
THE difSculties of feience have moreover produced various para- 
doxes. 
Confolidated filfures of rocks are often dihindlly vifible ; but by 
what means or power they have been broken^ is not eafily de- 
monftrated. 
All Spar is generated by eryftallization, in cavities filled up, 
nor is fpate ever prefent without rhombs; but why it is broken 
into rhombs, or how from a cubico-muriatic is produced a rhom- 
bic figure, is not very evident. 
Amiant is obferved to be regenerated from the earth of Talc, 
the caufe of which is obfcurc. 
That Molybdasnum is metallic cannot be doubted, and it has often 
been afferted to be impregnated with Zinc or Tin ; yet it is not eafy 
of proof. Jews-llones are found petrified in hollow cavities, ge- 
nerated from a fluid with fpar, of which they often entirely con- 
lift: but from what animal they have their origin is not fufficiently 
evident, fince the echini do not afford a fatisfadory elucidation. 
PRIMARY Salts have a peculiar and determinate figure, but when 
changed, often appear with a different but alike determinate figure; 
but from what mixture proper to themfelves, or from what extra- 
neous terrene mixture, the ftudent in this department has not been 
able to determine ; and fince metals are generated from fait by cryf- 
.tallization, Alchemifts have in vain laboured at the true transfor- 
mation of metals ; and this metamorphofis of falts fliall remain un- 
difeovered, fo long as Metalliirgills lhall negleft it, and turn their 
inveftigations towards earths only. 
SIMILAR Strata* of the earth are often obfervable in broken moun- 
tains; but it is not evident that they are all of the fame genus, or 
produced from the waters of the ocean: 
1. The lovvermoft ftratum of Sand-Jlone, 
2. The fecond ot Schiji. 
• The various flrata of earth are eonftantly obferved in equal order and dif- 
tance; and thefore this accretion of foil, io well kept dillinfl, fliould be ra- 
ther confidered as the operation of a fucceflion of ages, than the tumultuous 
jumble of the general deluge. Ramazz, mut. zjy. 
