VOLATILE OIL OP GAULTHERIA PROCUMBENS. 211 
ART. XXXI. — OBSERVATIONS ON THE VOLATILE OIL OF 
GAULTHERIA PROCUMBENS, PROVING IT TO BE A 
HYDRACID ANALOGOUS TO SALICULOUS ACID. 
By William Procter, Jr. 
Several years since the volatile oil of Spiraea ulmaria, 
(meadow sweet,) first obtained by Pagenstecher by distilling 
the flowers of that plant with water, was proved by Lowig to 
contain a hydracid, which possesses uncommon interest from 
the number of compounds it is capable of forming with other 
bodies. The discovery of hyduret of salicyle as a product of 
the decomposition of salicin, by Piria, and its identity with 
the hydracid in oil of Spiraea ulmaria, as since demonstrated 
by the exact analyses of Ettling,* have added much more 
interest to these proximate principles. 
The hypothetical radical called spiroil by L5wig, and 
salicyle by Piria, Liebig denominates salicule. This radical, 
combined with an equivalent of hydrogen, forms saliculous 
acid, which, united with bases, constitutes saliculites. When 
saliculous acid is oxidized by the agency of potassa, water, and 
heat, saliculic acid is formed, and its compounds are called 
saliculates. When saliculous acid combines with chlorine, 
bromine, or iodine, an equivalent of hydrogen is replaced 
by an equivalent of those elements respectively, and chloro- 
saliculic, bromosaliculic, and iodosaliculic acids are pro- 
duced. 
For several years past it has been supposed! that the vola- 
tile oil of the Gaultheria procumbens, either from the analogy 
of their odor or specific gravity, possessed similar properties 
with the oil of Spiraea ulmaria, without any steps having been 
taken to ascertain the correctness of the supposition. The 
* Liebig's Turner. 
VOL. VIII. — NO. III. 
fDr. Wood, U. S. Dispensatory. 
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