OF ARTS AND SCIENCES. 205 



The formation of this acid under these conditions can be explained by 

 the supposition tliat the acetate absorbed water from tlie atmospliere, 

 and became converted into the alcohol, which was then oxidized by 

 exposure to the action of the air ; and this view is supported by the 

 observation, that a product from the reaction of paraiodbenzylbromide 

 on sodic acetate dissolved in ordinary alcohol, when precipitated by 

 water, and the oil thus obtained allowed to stand exposed to the air in 

 a watch-glass, deposited crystals, which upon recrystallization melted at 

 70'^, and were, therefore, the alcohol. It must, however, be remembered 

 that this oil contained some of the bromide, and that the alcohol may 

 have been formed from this instead of the acetate. This conversion 

 of the acetate into the alcohol or acid seemed likely to render its puri- 

 fication so difficult that the experiment with argentic acetate was not 

 repeated. A similar formation of the substituted benzoic acid has 

 been observed in the attempts to purify parabrombenzylacetate. 



ParaiodhenzyJcyanide, C^H^ICH.^GN, was obtained by boiling the 

 bromide with alcoholic potassic cyanide, precipitating with water, and 

 crystallizing from alcohol. Its composition was established by the fol- 

 lowing nitrogen determination : — 



0.3523 gr. substance gave 17.83 cc. nitrogen, under a pressure of 

 736. mm. and a tempei'ature of 23°. 



Calculated for C^HglCN. Found. 



Nitrogen 5.76 5.67 



Properties. White plates with a pearly lustre, characteristic odor, 

 and no action on the eyes ; melting-point, 50.^'^ ; insoluble in water ; 

 readily soluble in alcohol, ether, benzole, carbonic disulphide, and gla- 

 cial acetic acid. 



Paraiodalphatoluylic acid, C^H^IGH^QOOH, was obtained by heat- 

 ing the cyanide with fuming hydrochloric acid to 100° in a sealed tube : 

 after four hours, the liquid on cooling became filled with flattened 

 needles, which were purified by crystallization from boiling water. 

 The composition of the acid was fixed by the analysis of its silver 

 salt. 



Properties. Narrow, tapering, white plates, often over two centi- 

 meters long, with an agreeable odor resembling that of sweet alyssum ; 

 melting-point, 135°, sublimes in branching needles at a somewhat 

 higher temperature ; but slightly soluble in cold, readily in hot water, 

 and in alcohol, ether, benzole, carbonic disulphide, and glacial acetic 

 acid. A mixture of potassic dichromate and dilute sulphuric acid oxi- 



