390 
time occupied by geological changes of which we see the result? 
Achange^Jf temperature, of moisture, of carbon, c acid m the 
air^ may^ot merely make our calculations somewhat maccu- 
ra 22 b We a lr\h"t rpfocess of formation of the more 
familiar strata of the globe is in great measure < 
to us; though the more we examine the s “ b £f t h at p evlil 
-v-li hp struck bv the proportion and fitness that prevan 
everywhere^and w£ch pofnt 'most clearly to a gmdmg power, 
Ia o h 3 r Tt"e 0 are h o«, f er r< 'deposits, however, which we cannot, as 
yet, JceTo their origin . 1 Iron ore is found in ^ . tone , • 
which are of almost pure oxide; the separation o : it m t 
„ tntp i s most difficult to account for. We do not Know uy 
cess the iron was thus collected together, instead of bein B , > 
=^^SSsftE*5 
the^separaTed^into 1 tlie°veiiis of the rooks where we now find 
* 
““.‘i 1 ' : wrmustTe" with the prodigal variety of nature 
if we may use the ^tVe’cUo^'o' ,SurTr"s 
mahe up 
the ma^of^the g^be; the proportioimte quantity of ^t^ rarer 
^ B -ral m P ass, and why do 
we find them distributed in small deposits, with no assign. 
^^^r"e rarer elements, but also of 
rr* 
nesia from a solution in water and carbonic acid, but 
