78 BACTERIOLOGY. 



disinfecting power than phenol. The cresols 

 are, however, so difficultly soluble in water 

 that their action is not sufficiently powerful to 

 destroy all bacteria, especially the spores. 



Since solution by means of mineral acids 

 affords strongly corrosive and destructive com- 

 pounds, an attempt has been made to convert 

 the cresols of the crude carbolic acid, which 

 are almost useless for purposes of disinfection 

 because of their slight solubility, into a form 

 soluble in water, in order to utilize thereby 

 their disinfecting power. Phenol and cresol 

 are easily soluble in soap solutions, hydro- 

 carbons difficultly so. If we start with a coal- 

 tar oil which contains much hydrocarbon and 

 little phenol, and mix it with soap and dilute 

 with water, an emulsion is obtained ; this is 

 the so-called creolin. If on the other hand 

 we take first a coal-tar oil which contains little 

 hydrocarbon and more phenol and mix this 

 with soap, and dilute with water, we obtain 

 a -solution ; examples of this are the disinfect- 

 ants sapocarbol and lysol. Mixtures of crude 

 carbolic acid and soap prepared in this way 

 turn to good account the disinfecting power of 

 cresol. If cresol, which is by itself barely sol- 

 uble in water, be mixed with the difficultly sol- 

 uble salts of the ortho-oxy-carbo- or ortho-oxy- 

 sulfonic acids, the mixture is soluble in water, 



