VOLATILE OIL OP GAULTHERIA PROCUMBENS. 215 
Oil of Gaultheria and Potassa. — When oil of gaultheria 
is added to a concentrated solution of potassa instant combi- 
nation takes place, and a crystalline substance results, which 
separates from the solution. Pressure between bibulous pa- 
per separates most of the adhering alkali; and by solution in 
a small quantity of hot alcohol it is deposited in six-sided 
tables by cooling. These crystals are transparent, nearly co- 
lorless, and are very soluble in water, and soluble in alcohol 
and ether. 
When dry, this salt is not affected by the air, but if mois- 
ture be present it becomes dark colored, and finally black. 
The acids decompose it, setting the oil at liberty. It is pre- 
cipitated white by the salts of baryta, lead, and zinc; yellow 
by nitrate of mercury; gray by the nitrate of silver; and 
bluish gray by protosulphate of iron. 
When an excess of oil of gaultheria is employed in crys- 
tallizing it from alcohol, the salt is obtained in acicular crys- 
tals, which decompose by solution in water — a portion of oil 
being liberated. 
Oil of Gaultheria and Soda. — The reactions of these two 
substances are similar to those with potassa. The soda salt 
is perfectly white, crystallizes in minute prisms, and is 
much less soluble in water and alcohol than the preceding 
£?alt. 
Oil of Gaultheria with Baryta. — When chloride of ba- 
rium is added to a solution of either of the two last salts, a 
white flocculent precipitate results. If to a transparent solu- 
tion of baryta in cold water, oil of gaultheria be added, and 
the mixture agitated, a white flocculent precipitate is also ob- 
tained. This, when washed with alcohol and dried, is the 
salt of baryta. When it is mixed with water acids decom- 
pose it — the oil being liberated. It is soluble in boiling 
water. 
Decomposition of the alkaline salts of oil of Gaultheria 
by heat — If protosulphate of iron be added to a cold solution 
