38 Prof. J. E. Reynolds. [Nov. 22, 



The first of these is a beautiful tetrathiocarbamide compound, whose 

 formula proved to be 



(H 5 N 2 CS) 4 NBr, 



which may obviously be written 



(H 4 N 2 CS) 4 H 4 NBr. 



This body separates from alcohol in fine masses of crystals resembling 

 sea anemones in appearance, which melt at 173 174, and begin to 

 decompose at 178 180. The synthesis of this substance was 

 effected by heating ammonium bromide with thiocarbamide. 



Several homologues of the above tetrathiocarbamidammonium 'bro- 

 mide were produced by synthetic methods ; some of these contain 

 chlorine or iodine instead of bromine. The following are examples of 

 the compounds formed in the course of this part of the investiga- 

 tion : 



(H 4 N 2 CS) 4 H 4 NBr, 



(H 4 N 8 CS) 4 H 4 NC1, 



(H 4 N 2 CS) 4 (CH 3 )H,NBr, 



(H 4 N 2 CS) 4 (C 2 H 5 ) 2 H 2 NBr, 



(H 4 N 2 CS) 4 (C 2 H 5 ) 3 HNC1. 



By the action of silver nitrate on the tetrathiocarbamidammonium 

 bromide the crystalline dithiocarbamide compound with silver bromide 

 was obtained 



(H 4 N 2 CS) 2 AgBr. 



This was subsequently produced by the direct union of thiocarbamide 

 with the pure silver haloid. The compound 



(H 4 N 2 CS) 2 AgCl 



was also obtained in fine crystals, as were other similar substances. 



A trithiocarbamide compound is also formed during the action of 

 ethyl alcohol on (H 4 N 2 CS) 8 SiBr 4 , but it is much more soluble than 

 that which first separates. It is also crystalline, and its analysis 

 and reactions lead to the formula . 



(H 5 N 2 CS) 3 Br,C 2 H 5 Br. 



Hitherto only mono- and di-thiocarbamide derivatives have been 

 known ; but the results above stated in outline prove that tri- and 

 tetra-thiocarbamide compounds are formed in presence of silicon 

 tetrabromide and certain other agents, which latter form addition 

 products with the condensed amide. 



