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pliasGü; are no longer possilile in a stable cquililiriuni. It is true 

 that Mr. de Bkuijn has noticed them several times, hut they 

 (]i sap pea red fit the appeai-ance of the solid phase. 



Mr. DE Bruijx has also deter- 

 mined several isothermals at higher 

 temperatures, where the isothermals 

 have forms as in fig. 1. As to 

 the connodal linos for the dilFe- 

 rent temperatures, it was proved, 

 that they intersect each other in 

 different manners or cover each 

 other within the limits of the faults 

 of analysis. In order to further 

 investigate this point several sec- 

 tions were determined, in v.liich the proportion of water and alco- 

 hol was the same, but the (piantity of (NH4)., SO4 varied. In accor- 

 dance with the situation of the connodal linos with respect to each 

 other Mr. de Bruijn found the following facts. If the proportion 

 of (K 114)2 SO4 is taken for the ordinate and for the abscis the 

 temperature at which two liquid phases become homogeneous or a 

 homogeneous liquid phase is divided into two others, we get, with 

 a greater proportion of alcohol, lines rising with the temperature ; 

 with a smaller proportion of alcohol, lines falling with the tempe- 

 rature, between the two, lines showing a maximum, which moves 

 toward a higher temperature with a greater proportion of alcohol. 

 From these different sections follows in accordance with the iso- 

 thermals given, that it is possible to have solutions of (Nll4)2Bn-' 

 in water and alcohol that are homogeneous at a certain temperatuie, 

 but divide into two layers both in case of a rise and of a fall in the 

 tomporaturc. Mr. pe Bruijn has made several of those solutions. 



II. The sijslctii: Pulds^/'iniicarljDiialc, victlnjlalkoliol and water. 



Xoxt to the two liquid phases 

 there appears in this system as 

 a solid phase the hydrate (KjC(>.)., 

 (IIoO), (at lower temperatures per- 

 haps a still higher hydrate). The 

 isotherm has here the form of fig. 

 2. RO and BS indicate the solu- 

 tions that can be in equilibrium 

 with (KnC0...\(Il20)„ ; SQ the 

 solutions in equilibrium with 



