VARICTY OF SUr.PHATB^OF Ll^fB. 
'il6 
VI. 
Chemical Examination of a supposed variety of Apatite or 
Native Phosphate <f Lime, from Aberdeenshire, in Scotland. 
By Amerigo Cabkall de Mello. {From the Author.) 
On flic classifi 
cation of ini- 
xieral bodies. 
- A S the philosophy of the subjects of the rainefal kingdom 
_ZaL must naturally be in a constant state of improvement, 
every attempt to extend its boundaries by new researches, can- 
not fail to prove useful to the progress of science. 
And although the science of minerals has of late been pro- 
digiously e.xtended, our knowledge with regard to the chemical 
constitution of a vast number of the inorganic bodies which 
compose the shell of our earth, is still confined within narrow 
limits j not only are we ignorant of the composition of a mul- 
titude of the most common fossils we tread under our feet, but 
even with respect to those with which men appear to be ac* 
quaintedj further information is required. ^ , 
The constitution of mineral substances being so widely different 
from that of organic beings, gives rise to such infinite varie- 
ties of forms and arrangements of principles, as will prq- 
bably for ever prevent, the mineralogist to establish his system 
upon constant and invariable characters. The formation of 
fossils being the result of simple combination of external mate- 
rials, aided by mechanical action, or effected by chemical affi- 
nity, must produce varieties of forms, which can only be 
arranged by arbitrary titles. 
It is thus that we see minerals so frequently removed from 
one class into another. Indeed, this methodical distribution 
of the subjects of natural history, whatever steps be taken, 
must, on this account, be constantly changeable, and cannot 
I 
be so absolute as those which belong to animals and vege- 
tables. 
The mineral of which I herewith subjoin the analysis, having 
been considered as a new variety of phosphate of lime, 
it has received a place as such among the native phosphates in 
the cabinets of mineralogists of this countiy. It was brought 
into 
