1 62 Scientific Proceedings, Royal Dublin Society. 



•i. By distilling clie carbon tetrachloride solution from the mixture to which 

 four molecular amounts of nitric acid had been added, a small amount of nearly 

 colourless crystals of tetryl was obtained, and by fractional crystallisation from 

 alcohol of the crystalline solid suspended in the aqueous portion we separated some 

 pure 2-4-6-trinitro-methylaniline from the impurity (probably tetryl) with which 

 it was mixed. 



SUMMAUY. 



1. Under the conditions of our experiments phenyl-methylurea formed no nitro 

 derivatives. When nitrous acid was present the phenyl-methylurea was converted 

 into methylaniline, and hence the nitro substances we isolated were in all cases 

 ■derived from the latter base. 



2. Nitrogen peroxide in the vapour phase converted phenyl-methylurea into 

 tetryl, but in solution it formed successively 4-nitro-phenyl-methyl-nitrosamine, 

 2-4-diuitro- and 2-4'6-trinitro-methylaniline. 



3. In the presence of urea nitrate, nitric acid had little, if any, action on phenyl- 

 methylurea, but in the presence of nitrous acid the phenyl-methylurea was 

 ■converted into phenyl-methyl-nitrosamine, 4-nitro-phenyl-methyl-nitrosamine, 2-4- 

 dinitro-methylaniline, 2"4'6-trinitro-methylaniline, and tetryl. 



Incidentally it was found that tetryl could be obtained in a good yield and in 

 a pure condition by the nitration of phenyl-methylurea or phenyl-methyl- 

 nitrosamine. 



4. So far as ease of nitration is concerned, phenyl-methylurea bears to sym- 

 diphenylurea a relation somewhat similar to that of ethyl- o-tolylurethane to 

 diphenylurethane. 



In conclusion we wish to state that the above research was undertaken at the 

 request of the Kesearch Section of Nobel's Explosives Company, to whom we are 

 indebted for a grant in aid of the investigation. 



