THE COLLOID-CHEMISTRY OF SOAPS 103 



The alkali concentration of Table XLIV corresponds with that 

 of tube 4 in Fig. 57 (Table XXVI). The non-dehydrating effects 

 of the concentrations of potassium chlorid employed are clearly 

 apparent by referring to Fig. 60 and Table XXX. While the 

 concentration of alkali alone leads only to gelation of the potas- 

 sium oleate. it will be seen in Table XLIV that the effect of the 

 potassium chlorid adds itself to this, wherefore the first tube in 

 the series shows a beginning dehydration which, with increase 

 in the concentration of the added salt, becomes progressively 

 greater until marked dehydration and separation from the clear 

 dis|x?rsion medium is evident in the last tube. 



Table XLV shows that such an additive effect is apparent 

 also when in the presence of a fixed concentration of potassium 

 chlorid different amounts of standard potassium hydroxid solu- 

 tion are added to the standard potassium oleate. While neither 

 of the substances when used alone and in the concentrations 

 prevailing in the first tube lead to gelation, the two together do 

 so. When comparison is made with the proper tubes of Figs. 

 57 and 60, it is also apparent that the secondary liquefaction 

 and the dehydration begin earlier when alkali and salt are used 



ther than when either is used alone. 



To complete this series, we add Tables XL VI and XLVII. 

 In Table XLVI the concentration of potassium hydroxid is fixed 

 and that of sodium chlorid varies, while in Table XLVII the 

 concentration of sodium chlorid is fixed and that of potassium 

 hydroxid varies. These tables should be compared with Tables 

 \ XVI and XLIX, or Figs. 57 and 70. Such comparison slums 

 that gelation with sule(|iient liquefaction and dehydration are 

 obtained earlier when the alkali and chlorid are present together 

 than when either is used alone in the concent ration chosen. When 

 (Tects of sodium chlorid are compared with those of potassium 

 chlorjd.it is a^ain apparent that t he sodium salt acts more power- 

 fully; in other word-, the systems are shifted toward the regions 

 of e&rlier gelation earlier dehydration and earlier -eparation. 



5. We next tried the effects of adding in e<|uimolar concen- 

 trations various salts possessed of a common acid radical but 

 different base*. We chosr chl<.< 



! \ III :,nd I Imduced :.- cheek* on Table 



XXX 60 and on the exj* -riinents al>out to be described) 



arc shown the effects of adding successively higher conccntra- 



