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[241 J 
XLII. Description of a portable Mineralogical Laboratory. 
By Freprick Accem, M.R.LA. F.L.S. Operative 
Chemist, and Lecturer on Chemistry and on Mineralogy 
and Pharmacy, 
ty, 
hae chemistry has in a manner changed its appearance, 
since its means of analysis have been increased, and since 
the instruments ef research have acquired their present 
high degree of perfection, new paths tor exploring the 
productions of nature have been opened, the art of ex- 
perimenting has been simplified, and become more fami- 
liar and easy. Most of the operations of chemical science 
which formerly demanded a regular laboratory, may now 
be performed on a small scale, with more perspicuity and 
expedition by the help of such instruments as most persons 
can command. 
Thus, however varied the objects of experiment may_be, 
and however numerous and different the products to be 
obtained may appear, the most costly materials may be 
used at a’ trifling expense in such pursuits. ‘The operator 
4s. enabled to observe the gradual changes of each process 
with more facility and:speed in the small way, than i the 
large; it\isein his power to urge, or to retard readily the 
operation at pleasure, and to ascertain cach step of the ex- 
periment, from beginning to end. 
Such advantages will be valued properly by those who 
know that the most experienced and most attentive che- 
mist meets with frequent accidents, by which both the ves~ 
sels and the products of the operations/are lost, because he 
has it not in bis power to ascertain the nature’of the results 
4s occasion may require. It is thus also that, among the 
furnaces of the jaboratory, mauy appearayces often pass 
away unnoticed, which aresreadily observed when the same 
operation is performed onthe table, and under the imme~ 
diate eye of the experimenter. Besides, most of those in- 
vestigations which in the large way require several days’ 
Jabour, can on a small scale be finished in afew hours. 
Tine heat of the most violent furnaces may instantly be 
produced by a stream of air, passing from 4 blow-pipe blad- 
der, on a piece of ignited charcoal, or through the flame of 
a candle or spirit lamp. By mearis of the brilhant flame of 
the lamp furnace, avast number of chemical operations may 
be performed, which thirty years ago would have required 
a series of complex furnaces. All the processes of diges- 
tion, the sublimation of salts, the solutions of earthy and 
Vol. 37. No. 156. April 1811. QO metallic 
