684 
the study of the ternary system NH, CNS — CS (NH), — H,O was 
taken in hand after the melting-point diagram had been determined, — 
it which a method of analysis was worked out which enabled us 
100" : 59) 
le NHCMNS sof NA,ONS. 4 CSWH, Al CIN i 
quantitatively to determine the ammonium sulpho-cyanate and the 
thioureum by the side of each other with sufficient accuracy. 
The solubility-isotherms found at 25° and the investigation of the 
eoexisting solid phases, in which the residu-method was applied for 
the determination of the binary compound (see fig. 2) afforded a 
proof for the validity of the conclusion drawn from the melting-point 
figure, so that the existence of the compound 1.4 may now be con- 
sidered as conclusively proved. 
Moreover the knowledge of the peculiar situation of the solubility 
isotherms led us to a simple explanation of the method of prepa- 
ration of thioureum from ammonium sulphoevanate according to 
Reyrorps and WEeRNER'), which method had been unaccountable 
up to now. 
The process of preparation is as follows: ammonium sulphocyanate 
is heated for some time up to 160°, then the liquid is poured into 
1) Journal Chem. Soc, 83, 1 (1903). 
