134? BORAX. 
(200), in the manufacture of white glass. It ought to 
be kept in well-corked bottles, as otherwise the crystals 
soon fall into powder. 
The following is a pleasing experiment, which shows 
a singular and almost instantaneous crystallization of 
Glauber's salt. Dissolve this salt by adding portions of 
it gradually to water kept boiling until the water will 
dissolve no more. Pour the solution, whilst boiling, 
into common medicine phials previously warmed, and 
immediately cork them. Set the phials in a quiet place 
without shaking them. The solution, when cool, will re- 
main perfectly fluid till the cork is taken out ; but the 
moment this is done, and the air is admitted, it will be- 
gin to crystallize on its upper surface, in fine satin-like 
crystals, which will shoot downward, like a dense white 
cloud. In this act so much heat becomes evolved as to 
make the phial feel sensibly warm to the hand. When 
the crystallization is complete, the whole mass generally 
becomes so solid, that, on inverting the bottle, not a 
drop of it will fall out. If the crystallization should not 
immediately ensue on opening the phial, this may in- 
stantly be effected by dropping into it a minute crystal 
of the same salt. The experiment may be exhibited 
any number of times afterwards, by merely placing the 
phial in boiling water, till the salt it contains be again 
completely liquefied; and letting it stand, as before, to 
cool. 
204. BORAX is a salt composed of boracic acid (28) and 
soda (200), and is imported chiefly from the East Indies, in 
the form of a brownish g?*ey, impure, shapeless salt, of sweetish 
taste ; or in detached prismatic crystals, each about an inch in 
length. 
Although borax has long been known as an article of 
traffic, there is scarcely any production witli the origin of 
which we have been, till lately, less acquainted. It is 
found in a native, though impure state, in a mountain 
lake, situated about fifteen days' journey from the capi- 
tal of'Thibet in the East Indies. This lake is so encom- 
passed with hills as to have no stream either falling into 
