PROXIMATE PRINCIPLES OF VEGETABLES. 
ammoniac; the latter escapes on the application of heat be- 
fore the borax begins to fuse. 
Fluorides. — Fluoride of sodium is decomposed by calcin- 
ation with chloride of ammonium; it is however with great 
difficulty. The layer of fused chloride of sodium protects 
the still-undecomposed fluoride from further decomposition 
by chloride of ammonium. Fluoride of calcium is still less 
easily decomposed. 
Bromides. — Bromide of sodium is decomposed, but not 
completely, by calcination with chloride of ammonium. 
When the treatment is frequently repeated, the residue con- 
sists principally of chloride of sodium, but always contains 
a considerable amount of bromide. 
Iodides. — Iodide of potassium is decomposed by ignition 
with chloride of ammonium ; but it is not entirely converted 
into chloride of potassium, even when the treatment is fre- 
quently repeated. 
It is remarkable, that not only is chloride of ammonium 
incapable of decomposing the bromides and iodides complete- 
ly, but also that it behaves exactly in the same manner to- 
wards fluorides, the partial decomposition of which by chlo- 
ride of ammonium was not to be expected. 
Nitrates. — Nitrate of potash is easily and entirely decom- 
posed by chloride of ammonium, and yields accurately the 
the amount of chloride of potassium corresponding to the 
salt. — Chem. Gaz. from Proc. of Berlin Academy. 
ART. XXIII. — ON SOME OF THE PROXIMATE PRINCIPLES OF 
VEGETABLES. THEIR NATURE, AND A NEW METHOD OF 
PREPARING THEM. By M. Lebourdais. 
In 1825 I commenced a numerous series of experiments, 
with a view to obtain the proximate principles I imagined 
must exist in the Columbo root, the bulbs of Scilla, the 
the leaves of Digitalis, of Ilex, the flowers oi &rnica, &c. 
