352 PROCEEDINGS OF THE AMERICAN ACADEMY 



in the air, precisely as is the case with oleic acid. The hypogajic 

 ether, and the copper and baryta salts possess the same properties 

 as the corresponding compounds of oleic acid. 



" In order to determine the result of the action of nitrous acid on 

 this acid, we instituted the following experiments. 



" A portion of the acid, partly oxidized by the air, was slightly 

 warmed to render it completely fluid, while a rapid current of nitrous 

 acid gas was conducted through the liquid. The product, after being 

 allowed to stand a week in a well-closed vessel, yielded, on recrys- 

 tallization several times repeated, an acid which melted at 37-38° C, 

 was unchangeable in the air, and very soluble in alcohol, separating 

 from the solution in a crystalline form. 



On analysis, the following results were obtained : — 

 Calculated. Found. 



Csa 75.59 75.41 75.57 75.59 



H30 11.81 12.01 . 11.91 11.89 



O4 12.60 



" Hence this acid is an isomeric modification of the hypogasic 

 acid ; we have proposed for it the name of Gseidinic acid. 



" Gceidinic ether is a colorless oil, soluble in alcohol and ether, 

 which solidifies at low temperatures, and can be distilled without de- 

 composition. 



" GcBidinate of potassa is easily soluble in water and alcohol, and 

 can be obtained in pearly crystalline scales. 



" Gczidinate of baryta is a white powder, insoluble in water, more 

 soluble in alcohol. 



" Gceidinate of copper is a green powder, with difficulty soluble in 

 water or alcohol, which melts before decomposition. 



" Gceidinate of silver is a flocky precipitate, insoluble in alcohol or 

 water, soluble in ammonia, and which is readily blackened on exposure 

 to the light. 



" On comparison of this new acid with elaidic acid, the product 

 of the action of nitrous acid on oleic acid, we find a perfect corre- 

 spondence in their properties, and also that the relation between the 

 properties of hypogseic and gfeidinic acids on the one hand, and oleic 

 and elaidic acids on the other, is quite similar. 



" The oleic and hypogeeic acids are both, as we have seen, readily 

 oxidized on exposure to the air, as are also the ether compourWs ; and 

 farther, neither the acids themselves, nor their ether compounds, can 

 be distilled without decomposition. 



