282 ODOROGKAPHIA. 



plants of the Composite Order. It is also found in many animal 

 oils and other animal secretions. It is a frequent product of 

 the oxidation of f.'its and of the putrefaction of albuminous 

 substances. 



The valerianic acid prepared from valerian root is less commonly 

 employed than the same acid prepared artificially by either of the 

 following processes : — 



1. A mixture of fusel oil (hydrated oxide of amyl, called also 

 " oil of potato-spirit, or grain-oil"), with about 10 times its weight 

 of (|uicklime and potassium hydrate in equal proportions, placed 

 in a glass flask, heated first to 170^ C, and the temperature 

 gradually raised to 200^^ C, and then kept heated for 10 or 12 

 hours, by means of a bath of oil or fusible metal ; the nearly white 

 solid residuum is mixed with water, an excess of sulphuric acid 

 added to the mixture, and the wdiole subjected to distillation ; the 

 distillate is supersaturated with potash (or the condensed vapour 

 may pass into a receiver containing a solution of carbonate of soda), 

 evaporated nearly to dryness to dissipate any undecomposed potato 

 oil, and then mixed with weak sulphuric acid in excess ; a light 

 oily liquid (terhydrated valerianic acid) separates, which by 

 cautious rectification, yields at first water containing a little acid, 

 and afterwards pure monohydrated valerianic acid, which is 

 perfectly identical with that prepared from valerian root. 



2. From sodium valerianate, wdiich is perhaps the most 

 economical process. Dilute 6J fluid ounces of commercial 

 sulphuric acid with J pint of w^ater ; then dissolve 9 ounces 

 potassium dichromate in 3J pints of water with the aid of heat ; 

 when both solutions have cooled put them into a matrass, and 

 having added 4 fluid ounces of fusel oil, shake them together 

 repeatedly until the temperature, which first rises to 150° Fahr., 

 has fallen to 80" or 90° F.). A condenser being connected, next apply 

 heat so as to distil over about -l pints of liquid; saturate this 

 exactly with a pint or q. s. of solution of caustic soda, separate 

 the liquid from the oil which floats upon the surface, and evaporate 

 it until the residual salt is partially liquefied. The heat being now 

 withdrawn, and the salt concreted, this last, whilst still warm 

 is to be immediately divided into fragments and preserved in well 

 stoppered bottles if not intended for immediate use. The 

 valerianic acid can be separated from this salt as described in the 



