Testing Germicidal Value of Liquids 



263 



the top. When an experiment is about to be made the tempera- 

 ture of the water in the pail is taken, and if above or below 2o°C., 



:S^VV^g 



Fig. 84. — Water-bath showing position of holes for seeding tubes and ther- 

 mometer in place (Anderson and McClintic, in Bulletin No. 82, Hygienic 

 Laboratory). 



~ — 



■F'g 85. — Cross section of water-bath showing seeding tubes in place (Ander- 

 son and McClintic, in Bulletin No. 82, Hygienic Laboratory). 



it is brought to the desired temperature by the addition of either 

 hot or cold water. When the proper temperature has thus been 



