156 PROCEEDINGS OP THE AMERICAN ACADEMY 



On the other hand, the product obtained from succinosuccinic 

 ether is alone to be regarded as oxiinidosuccinic acid, 



C0 2 H-ONOH 



I 

 C0 2 HCH 2 



That, however, the one product can, by addition of water or of 

 HC1, and the splitting off again of these reagents, be converted 

 into the other, is readily seen. 



With regard to the so called geometrical isomeric dioximido- 

 succinic acids,* it can be said that the isomers discovered have not 

 been proved to have the same constitution. The above observa- 

 tions in the case of the oximes of benzil, as well as the possibility 

 of lactone formation, complicate matters here to such an extent 

 that much more experimental material must be at hand in order to 

 decide the question. 



B. On the Nature of Prussic Acid. 



From the above experiments, and the work on acetacetic ether, 

 it has become very probable that prussic acid has the formula 

 HN=C=, and, consequently, that the metal in its salts is bound to 

 nitrogen, M-NO. 



The physical properties of prussic acid, boiling point 26. °2, 

 specific gravity 0.697, and the poisonous properties, all tend to 

 show that this substance is the first member of the isonitrile, 

 R-N=0, series. At present experiments are being undertaken with 

 the object of obtaining the actual formonitrile, H-ON, by the re- 

 duction of cyanogen chloride or iodide. It is to be expected that 

 this substance will be neutral, and that it will possess a much 

 higher boiling point and specific gravity than prussic acid. 



Potassium cyanide, f K-N=C=, reacts with alkyliodides, owing to 

 the energy of the bivalent carbon atom present, chiefly as follows: 



KNO + RI = KNO ( = N^C-K + KI. 



X I 



Addition Product. Alkylcyanide. 



* Soderbaum, Ber. d. Chem. Ges., XXIV. 1215. 



t It would be more logical to call this substance potassic isocyanide, since it 

 does not belong to the cyanogen (-ON), but to the isocyanogen (-N=C=) com- 

 pounds. It is however questionable whether such a change would be feasible 

 at present. 



