120 L. Remsen on Ethyl succinate. 
which would probably be identical with the two known forms 
of nitrosulphobenzoic acid. According to the conditions then, 
we would have data which would enable us to determine the 
constitution of these latter acids ; for we should thus fix the posi- 
tion, first, of the sulpho-group with reference to the carboxyl, 
and eres that of the nitro-group in one and the same com- 
n 
ound. 
I shall endeavor to prove the feasibility of this method of in- 
vestigation, as soon as possible. It is well to remember, how- 
ever, that Mulder* has already tried to obtain a nitrosulphoben- 
zoic acid by the action of sulphuric acid on ordinary (meta) 
nitrobenzoic acid, and that no such product resulted. Possibly 
the isomeric nitrobenzoic acids may yield more satisfactory 
results. 
Il. On the Action of Potassium on Ethyl succinate. 
n s 
In a pure condition, it forms long, flat, beautiful needles of a 
slightly yellowish color, instead of yellow Jaminz. It may 0° 
boiled ‘with alcohol or water without undergoing change. Whet 
sodium-amalgam is added to the alcoholic solution, a very rapid 
change takes place. A bright red precipitate is formed, which 
* Annalen der Chemie u. Pharmacie, xxxiv, 297. 
+ Ibid, xlix, 192. 
