92 SOAPS AND PROTEINg 



of the alkali is shown in the upper row of Fig. 55. Within an 

 hour after adding the potassium hydroxid all the soaps began 

 to swell and to become covered with gelatinous films. This 

 change to potassium oleate was particularly rapid in the mag- 

 nesium and lead soaps. But it occurred in all, so that after an 

 hour enough potassium soap was formed to make the liquids 

 covering the metallic soaps show permanent foams. 



These changes occur in the cold and even when the reaction 

 mixtures are not stirred. Heating and stirring, however, hasten 

 the process. In either event a high degree of reversion is obtained 

 as indicated by the lower row of Fig. 55, which shows the appear- 

 ance of the soap mixtures after standing at room temperature 

 for forty-eight hours. So much potassium oleate had formed 

 that all the systems were highly gelatinous. 



A similar reversion from the stearates of the alkaline earths 

 and the heavy metals into sodium stearate is shown in Fig. 56. 

 The upper row shows the vials with their molar equivalents of 

 the different stearates prepared as described in Table IV (and 

 Fig. 3), just after 10 cc. normal sodium hydroxid had been added 

 to them. The actual amounts of soap in the vials were as follows : 



Magnesium stearate 9 . 60 grams 



Calcium stearate 7 . 05 grams 



Mercury stearate 8 . 65 grams 



Lead stearate 7 . 30 grams 



Barium stearate 5 . 87 grams 



After addition of the sodium hydroxid the mixtures were kept 

 warm for one hour at 75 C. The appearance of the same soap 

 mixtures forty-eight hours later is shown in the lower row of 

 Fig. 56. The reversion to sodium stearate is so great that all 

 the mixtures are now solid gels. 



2 



These experiments on reversion in soaps are of chief interest 

 to us because the soaps in their colloid-chemical behavior are like 

 the proteins of the living cell. The heavy metal soaps are like 

 the heavy metal proteinates which are produced when the living 

 cell is poisoned with lead, mercury, etc.; and just as the heavy 

 metal soaps may be converted into those of the lighter metals, 

 cells poisoned with heavy metals may be aided in their restoration 



