of the six types are shown below: 



Type Type Type Type Type Type 



I II III IV V VI 



KH2PO4 K2SO4 KNO3 K2SO4 KNO5 iai2P04 



Ca(N03)2 Ca(N03)2 Ca(H2P04)2 Ca(H2P04)2 CaS04 CaS04 



MgS04 Ms(H2K)4)2 MgS04 Mg(N03)2 Mg(H2P04)2 Hg(W03)2 



Twenty-one different sets of proportions of the 

 three/-3alla,were to be tested for each solution type ^ these 

 sets of salt proportions being conveniently shown by the 

 \aniform arrangement of twenty-one points on a triangular 

 diagram, such as v<as first used in this sort of work by 

 Schreiner and Skinner. The plan defined the several solutions 

 of each type in terms of molecular proportions of the three 

 main constituent salts. The solutions are designated by 

 convenient symbols referring to the serial number of the 

 row of the diagram in which any solution is represented 

 (always counting from below upv^ard), and to the serial 

 number of the solution as represented in the row (alv/ays 

 co\inting from left to right. Thus RIS2 denotes the second 

 point in the first (lowest) row of the diagram, which 

 represents an equilateral triangle with one side ha- izontal 

 and at the bottom. A Roman numeral prefixed to one of these 

 symbols -p^^^^yo^ denot^ the serial nuriber of the solution type 

 as above defined. If tVie three salts are always arranged iri 

 the same order, according to their cairns, the twenty-one 

 different symbols (representing the different sets of salt 



