DAIRY BACTERIOLOGY 81 



A plain slide may then be substituted for the stage 

 micrometer and all measurements taken by means of 

 the ocular micrometer. 



A table may then be constructed in the following 

 manner which will save time in calculating the meas- 

 urement of objects : 



.5 division .001923 m.m. 



.75 division .002888 m.m. 



1.00 division .003846 m.m. 



1.25 division .004825 m.m. 



1.3 division .005012 m.m. 



1.5 division .005785 m.m. 



1.75 division .006748 m.m. 



2.00 division .007712 m.m. 



2.25 division .008676 m.m. 



2.5 division .009640 m.m. 



2.75 division .010604 m.m. 



3.00 division .011569 m.m. 



Prepare a clean cover glass and place thereon a 

 drop of water. Transfer a minute portion of decayed 

 material, starter, or clabber milk, and spread uni- 

 formly over the surface of the glass and allow film 

 to dry. When dry, pass cover glass, smeared surface 

 upward, three times through a Bunsen flame at 

 about the rate of a pendulum of a clock. The heat 

 coagulates the albumen around the bacteria and fixes 

 them firmly to the glass. Place a drop of staining 

 solution prepared from anilin dyes (gentian-violet, 

 basic fuchsin, and methylene blue, are most commonly 

 used) on the glass and allow stain to remain for from 

 two to ten minutes, depending on the strength of the 

 staining solution and the kind of bacteria. Rinse in 

 water. Dry the unsmeared side on filter paper, 



