b39 



Da with water to free il IVoni its motlier-siihslniice. as lliis will 

 lead (o «iecomposilioii. 



When we wisli to examine accurately what will take place when 

 we bring together D^ and water, we must consider which spaces 

 of the pyramid are intersected hy the line D^T. From this amongst 

 others the following is apparent. When we add D^ to water, then 

 firstly unsaturated solutions arise, which are represented in fig. 1 

 by the point W. (In this it is to be considered that tig. 1 is the 

 projection of the spacial representation and that point W is the 

 projection of the line Da,T). 



With further addition of D^ the solution W arises, which can be 

 saturated with D^.^.j (this Dj.j.g, however, is not yet present as 

 solid phase) consequently the solution W of the saturationsurface iqlk. 



With further addition of Da now Dj.j.g is separated and the 

 solution traces in fig. 1 the straight line Ws, this straight line is the 

 projection of a curve situated on the saturationsurface iqlk. When 

 we add so much Da that the solution attains the point s, then, 

 further addition of Da will no more change the solution and there 

 is formed : 



D J. 1. g -|" I^;i + solution s. 



When we wish to examine wdiat will take place wdien we bring 

 together in variable quantities K^ SO^jCuClj and water, then we must 

 intersect the spacial representation by the plane K^SO^ — CuCl^^ — T. 

 When we bring together KCl — Cu SO4 and water in variable 

 quantities we must draw the plane K^ Clj — Cu SO4 — T. 



As the manner, in which these sections with the saturationsurfaces, 

 saturationlines and the different spaces can be obtained, was already 

 discussed previously ^), we will not apply this method now. 



In tables II and III we find indicated the compositions of several 

 solutions; we have deduced with the aid of the restmethod graphically 

 the solid phases with which these solutions are saturated. 



In table II the compositions are expressed in percentages by weight ; 

 of the four salts Cu SO^,Cu Cl^, K^SO^ and K^ Ci^ ; only three at the 

 same time are given. This is sufficient also because, if we wish to 

 express the composition also in the fourth salt, it may be done in 

 infinitely many ways with the aid of the reaction-equation 

 Cu SO, + K, CI, :^ K, SO, + Cu CI, 



For this the quantities of the substances which take part in the 

 reaction must be expressed in quantities by weight. 



1) V. A. H. ScHREiNEMAKEBS. Zeitschr. f. Phys. Clicm. 66 G99 (1909). 



