( 260 ) 



iiitnites of llie last group any mixed crystals at all oi- olse only to 

 a small extent and in any case they do not enter into chemical 

 combination. 



As regards the relation of AgNOj to the nitrates of the second 

 group, the only system examined up to the j>resent (by van Eyk) 

 was that consisting of AgNO, + TlNOg in which a compound in the 

 proportion 1:1, was formed. To complete our knowledge in this 

 direction, the systems NH, NO, -f AgNO, and KNO, -f AgNO, have 

 been investigated by Zawidzki and Ussow and the results are com- 

 prised in the Figures 1 and 2. 



A^y^, ^'j'^"^ 



A'A'r'j 



Fie. 1 and 2. 



The first system is interesting on account of the fact that with 

 NH^ NO, four and with AgNO, two solid phases succeed each other 

 which, starting from the melting-point, we will designate by Am 



1 — 4 and Ag 1 



-2. 



It now appears that in the case of mixtures of the two salts the 



