BROMINE IN MINERAL WATERS. 
195 
very evenly spread, in order that the resistance offered to 
the water may be equal throughout; and, for this purpose, 
the wood must be put into the vessel in small quantities at 
a time. A very important point is, to have the wood ground 
or rasped of a uniform size, without fine dust, as the parti- 
cles of this latter are apt to adhere together, and offer great 
resistance to the water at certain parts; thus preventing the 
colouring matter from being extracted therefrom. I have 
found that the wood spreads much better by previously 
wetting it. 
For some other woods, such as Lima and Pernamcubo 
woods, and other red dyewoods, 600 quarts of water, in- 
stead of 450, must be employed, as the colouring matter is 
not so easily extracted. Quercitron cannot be operated upon 
as it is too fine a powder. Cochineal does not succeed, as 
it swells so much on coming in contact with boiling water, 
that, in an experiment I made, I thought it would have 
burst the boiler. 
This apparatus is, however, very advantageous for the 
woods above mentioned, if the directions given are care- 
fully followed. — Chemist, from Newton's London Journal. 
ART. XXXVIII. — ON THE QUANTITATIVE ESTIMATION OF 
BROMINE IN MINERAL WATERS. 
By M. Heine. 
[This process is described in a work bearing the title, 
" Chemical Investigation of the Brines, Salts and residues 
of the Graduation Works in Saxony and Westphalia." 
Hitherto we possessed no accurate quantitative method for 
the determination of this important substance in mineral 
