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1829 .] 
Thoughts on Mineralogical Systems. 
it would be a pity to relinquish it. These two characters are, however, after all of but 
limited application ; and a very large number is left which are neither soluble in 
water, or acid, and to which no character derived from the colour of the powder either 
is applicable : to enable us to distinguish these into sections or subdivisions, more 
or less extensive, the blowpipe comes to onr assistance. 
16. The right management and skilful application of this instrument of chemical 
research is the true test of an accomplished mineralogist. It is with its accom- 
paniments a complete laboratory in miniature, and scarcely an experiment that can 
be performed in the one, but may also be resolved with the other. If the answer ob- 
tained be not equally exact as to the particulars, yet it is always sufficiently so to sa- 
tisfy all the demands of the mineralogist. What this little instrument is capable of, 
may be seen by the feats of flahn, the founder of this microscopic chemistry. He 
was in the habit of exhibiting by its means the iron in apiece of paper, or the alkali and 
silex in a straw. Professor Berzelius’ work on the use and application of this in- 
strument is a treasure to the mineralogical student ; and he will find in that work 
knowledge that cannot be valued too highly. It is, however, to be regretted, that this 
distinguished philosopher was so biassed by His theoretical notions, regarding che- 
mical combination, as to adopt an arrangement which to the student must be worse 
than useless. The singular contradiction too of founding a synthetical arrangement 
on observation with an instrument, the character of which is eminently analytical, 
seems to have completely escaped him. 
1 7. When we submit a mineral to the action of the blowpipe, either an effect is 
produced or not. In the former case it may be of various character. Thus the mine- 
ral may fuse quietly and without difficulty ; or it may fuse with intumescence ; or 
with difficulty ; or it may he infusible ; although a certain effect is produced. This 
latter may either consist in decrepitation ; exfoliation; disintegration; or there may- 
be change of properties without sensible phenomena. In the case of fusing, the 
result may be a colourless or coloured glass ; an enamel coloured or uncoloured ; a 
scoria ; or a bead of metal. With regard to the minerals which remain still unchanged 
when exposed to its action, wc are not entirely without resources. We can add to 
them certain reagents, and by the effect of these distinguish one from another. Car- 
bonate of soda, borax, and phosphate of soda are those most commonly employed; and 
the result with each of these, being examined, will scarcely permit of doubt witli re- 
gard to the name of the substance under examination : the discrimination even 
of species may be thus brought under its dominion. 
18. But our resources do not stop with the mere use of the blowpipe, for a com- 
plete system of microscopic chemistry, has been gradually established to aid and 
assist in doubtful cases. In this department, the late celebrated Doctor Wollas- 
ton shines conspicuous, for the ingenuity and precision of many of his methods. 
Mr. Smithson has added largely to the subject, and to us appears to have left little 
to desire. His paper on the detection of the several acids, inserted in the Annals of 
Philosophy, is extremely valuable to the mineralogical student, whom it enables to 
make in a few minutes as unexceptionable a qualitative, if not quantitative 
analysis, as the chemist could in several hours. In fact we consider witiuhis aid, 
added to all those w f e have detailed, the tyro need never be at a loss for the name 
ofa mineral, if it have one; or for the knowledge that it is a new species, if it be not 
as yet really named. To collect and digest into a system all the facts as yet known, 
and determine a few new ones when there is doubt or discrcpraucy, is all that is 
wanting. And he w'ho will execute such a task will do more for the progress of 
mineralogy than has been yet effected by any single work. 
19. To illustrate all that I have said, and show the application and use of very 
heterogeneous characters in discriminating minerals, I shall conclude this rather 
long paper with a sketch of a synoptical arrangement drawn up for my own use. 
The skilful mineralogist will perceive many errors and many deficiencies, and I am 
sensible of many myself ; but it will serve to show, how valuable such au arrange- 
ment would be if correctly executed. It is my intention hereafter to improve it as 
much as possible, and I shall therefore be obliged to any of the readers of the 
Gleanings for any hints to this effect. 
20. In this table I have not used any of the usual terms of classes, orders, or ge- 
nera. We know that with the exception of the species none of these determinations are 
to be found in nature, and in fact logicians will tell us that even to the use of the latter 
term in mineralogy, there are well grounded objections. My synopsis being founded 
on the dichotomous method, has only the latter terms co-ordinate, i. e. the 
species ; but this is an additional reason for urging its utility. In reality it would lie 
easy to apply such distinctions to my table, and thus conceal its dichotomous nature; 
but, in my opinion, this would be to circumscribe its utility', and take from its clear- 
