256 



PAINT TECHNOLOGY AND TESTS 



removed and used for making cultures. In each case the sur- 

 face of the section under test was washed with 100 c.c. of dis- 

 tilled, sterilized water. The washings which dripped from the 

 surface were collected in a graduated flask. One c.c. of the 

 washings was used in each case, admixed with bouillon and again 

 with agar-agar. The enormous development of bacteria in the 

 bouillon, treated with the washings from the wall-papered sur- 

 face, was sufficient evidence to convince one of the greater 



DEVELOPMENT OF BACTERIA IN BOUILLON SOLUTIONS 

 Note Practical Freedom of Note Milky Appearance of 



Bacteria in Clear Bouillon 

 Solution Treated with 

 Washings from Sanitary 

 Wall Paint 



Solution Due to Heavy De- 

 velopment of Bacteria in 

 Bouillon Treated with 

 Washings from Wall Paper 



sanitary value of the wall paint, the washings from which gave 

 a culture practically free from bacteria. The colonies of bac- 

 teria shown in the petri-dish test made of the washings from 

 wall paper further supports these findings. It will be noticed 

 that the tests made from the washings of the wall paint show 

 practical absence of bacteria, and was clear, as was the bouillon- 

 solution test of the paint. The washings from the wall paper 

 showed active development of bacteria, both in the bouillon and 

 agar tests. 



