OF THE MEADOW-SWEET. 155 
however, is only a sign for a certain expression, and thus considered it is 
perfectly indifferent what name may be chosen for any substance. 
- Hydrospiroilie Acid. 
The fluid oil of the blessoms of the Spirea Ulmaria is hydrospiroilic 
acid. This may be obtained by distilling the flowers with water ; about 
as much water is to be distilled off as was originally employed. 
‘The product of the distillation is however subjected to a redistillation 
till about 4th is come over in the receiver. A concentrated aqueous so- 
lution of the oil is thus obtained, and the oil itself, though only in very 
mainute quantities. The oil is heavier than water, is of a light yellow 
colour, and possesses the odour of the blossoms in a very great degree. 
It mixes in all proportions with alcohol and ether, and is slightly so- 
luble in water. It causes a burning sensation on the tongue. The fumes 
which come over during the distillation of the oil first render litmus- 
paper green, and then bleach it. The aqueous solution of the oil first of 
all slightly reddens tincture of litmus, and then deprives it of its colour 
excepting a greenish shade. It is inflammable, and burns with a shining 
smoky flame. Ifthe oil be passed through a red-hot tube containing 
pieces of iron, neither ammonia nor prussic acid is obtained nor can the 
formation of any sulphuret of iron be detected. The oil does not ex- 
perience any change either in dry or moist oxygen gas; it volatilizes 
unchanged. It solidifies at a temperature of —20°*. Its boiling-point is 
about + 85°*, when it evaporates entirely without leaving any residue. 
With the bases of salts, namely, with the alkalies and alkaline earths, 
it easily combines, forming insoluble or difficultly soluble compounds. 
Concentrated sulphuric acid converts the oil into a black carbona- 
ceous mass. Chlorine and bromine decompose it instantaneously, hy- 
drochloric or hydrobromic acid and chloride or bromide of spiroil being 
formed. Nitric acid, if not too concentrated, immediately forms spiroilic 
acid; if however the acid be very concentrated and fuming, it imme- 
diately changes it into a yellow, very volatile, bitter-tasting compound, 
having the appearance of butter. 
The experiments on the composition of the anhydrous oil, as well as the 
other compounds, were made in the usual manner with oxide of copper. 
0-290 grms. of the oil gave 0°694 carb. acid 19189 carbon 
0-290 ————_—___—_——- 0°14:5 water 16°10 hydrogen; 
according to which 290 parts of the oil contain 
CA TOLLE ae eee 191°89 orin 100 parts 66°17 
Hydrogen ......,.. 16°10 ————_ 5°55 
Oxyeen.-...- Se 82°01 — 28:28 
290:00 100:00 
ne * Probably Centigrade.—Transiaror. 
