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. 



Hydrospiroilic Add. 



The fluid oil of the blossoms of tlie Spireea 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 -i-th 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 

 minute 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 aether, 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. If the 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 -f- 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 191 '89 carbon 



0-290 0-145 water 16-10 hydrogen; 



according to which 290 parts of the oil contain 



Carbon 191 -89 or in 100 parts 66- 17 



Hydrogen 16-10 5-55 



Oxygen 82-01 28-28 



290-00 10000 



# Probably Ckntigradc-w-TRANiiAioK. 



