152 



SOAPS AND PROTEINS 



solid. But as soon as the temperature is raised sufficiently the re- 

 sulting liquid colloid systems emulsify splendidly. The matter is 

 illustrated for the case of sodium palmitate in the right-hand bottle 

 of Fig. 89. In this 60 cc. cottonseed oil were ground into 20 cc. 



m/16 "solution" of the soap in a hot water bath. At this 

 temperature a fine emulsion results. As soon, however, as the 

 temperature is allowed to drop to 25 for a few hours the system 

 cracks, as shown in the left-hand bottle of Fig. 89. If, however, 

 the temperature is maintained above the liquefaction point of 



