36 Proceedings of the Royal Irish Academy. 



of aniline obtained, besides the phenyl derivatives of mucamide, two 

 bodies of neutral character, one of which he regards as phenyl-pyrrol 

 C4H4 (CgHs) N. The second, which is only formed in small quantity, 

 corresponds to the formula CisHulS's. For this he proposes the consti- 



tutional formula C4H4 -C^ • From toluidine mucate he obtained 



only the homologue of this latter substance, CigHiglN'n, but no tolyl- 

 pyrrol. In phenyl-pyrrol it is highly probable, from the nature of 

 the reaction, that the group CgHs remains in connexion with the 

 nitrogen, and Kottnitz argues, by analogy, that the same position must 

 be assigned to the residue ethyl in Lubawin's ethyl-pyrrol. That this 

 cannot be the case will be rendered evident by the results of my expe- 

 riments. 



The plan of procedure which I have adopted is essentially that of 

 Ivottuitz. I have, however, experimented in addition with secondary 

 and tertiary monamines, in view of the possibility of obtaining di- and 

 tri-derivatives of pyrrol. In this respect my expectations have not 

 been fulfilled, and thus the view of Wichelhaus and of Baeyer and 

 Emmerling, viz., that pyrrol does not contain the residue jSTHa, has 

 received strong confirmation. I have, however, succeeded in pro- 

 ducing a series of bases derived from pyrrol, besides other allied bodies 

 which have no analogues amongst those described by Kottnitz. 

 These I proceed to describe. 



Distillation of Ethjlammonimn Mucate. 



This salt is easily formed by bringing together solutions of ethyl- 

 amine and mucic acid in equivalent proportions. The acid is rapidly 

 dissolved with development of heat, and on evaporation and slow 

 cooling the mucate is obtained in large, transparent, slightly oblique, 

 rhombic prisms, which are freely soluble in water, less so in alcohol. 

 These appear to correspond to the formula CsHioOs . I^K^ (C3II5) 

 + 8 II2O. They efiloresce on exposure to air, quickly losing the whole 

 of their water of crystallization. If dried in the water bath, the salt 

 experiences slight dissociation, some ethylia being given ojff. The 

 same occurs when a concentrated solution of it is boiled. The crystals 

 are, therefore, best dried in vacuo over sulphuric acid. When crys.tal- 

 lized from water at a high temperature, or from strong alcohol, the 

 salt is deposited in the anhydrous Form. A determination of the 

 ethylia evolved on heating the dried salt with caustic potash proved it 

 to have the composition CeHioOs, 2NH2C3HS. 



Exposed to heat, mucate of ethylia first melts, and then decom- 

 poses with intumescence. To obtain its distillation-products direct 

 heating over the lamp is not advisable. The operation is advan- 

 tageously conducted in a long-bodied retort, or, better still, in a tall 

 and thin-sided bottle, secured in a paraffin bath furnished with a 



