490 



Analysis of the yellow crystals, dried over sulphuric acid, led to 

 the formula 



C 26 H 20 NPS 2 , 



which shows that they are formed by the simple union of the two 

 substances placed in contact : 



Sulphocyanide Triethyl- New compound. 

 of phenyl. phosphine. 



If we consider urea as a diamine derived from diammonia by the 

 substitution of the diatomic molecule carbonyl (C 2 O 2 )" for 2 equivs. 

 of hydrogen, 



(0,0 



Urea C 2 H 4 N O 2 = H 2 I N 2 , 



the simplest perhaps of the many views brought forward regarding 

 the constitution of urea, the new substance, which formation as well 

 as chemical deportment essentially characterize as an analogue of 

 urea, may be represented by the following formula : 



(C 2 s 2 y ] 



C 26 H 20 NPS 2 = (C 4 H 5 ) 2 NP; 

 (C 12 H 5 )(C 4 H 5 )J 



that is, urea, the oxygen of which is replaced by sulphur, the hydro- 

 gen by ethyl and phenyl, and lastly, half the nitrogen by phosphorus. 



The formation of this compound presents considerable interest, not 

 only as an illustration of the remarkable persistence of the type urea, 

 but also as furnishing the first unequivocal instance of the formation 

 of ureas containing no longer any unreplaced hydrogen, the existence 

 of which had as yet remained doubtful. 



The new urea forms, as I have stated, a series of well-defined beau- 

 tifully crystallized salts. Its solution in warm hydrochloric acid 

 solidifies, on cooling, into a crystalline mass, which, when recrystal- 

 lized from warm water, is obtained in splendid needles of a bright 

 cadmium-yellow colour, often several inches in length. They are 

 decomposed at 100 C., and must therefore be dried over sulphuric 

 acid in vacuo. Analysis proved them to contain 

 C 26 H 20 NPS 2 ,HC1. 



The solution of this salt yields with dichloride of platinum a bright 

 yellow precipitate, which under the microscope is found to consist of 



