120 



DEMONSTRATING BACTERIA IN TISSUES 



4. Place the slide in a wire rack (Fig. 75), section 

 downward, in the "hot" incubator for twelve to 

 twenty-four hours. At the end of this time the section 

 is firmly adherent to the glass, and is treated during 

 the subsequent steps as a "fixed" cover-glass film 

 preparation. 



NOTE. If large, thick sections have to be manipulated, or if 

 time is of importance or acids are used during the staining 

 process, it is often advisable to add a trace of Mayer's albumin 

 to the alcohol before floating out the section. If this substance 

 is employed, a sojourn of twenty minutes to half an hour in the 

 "hot" incubator will be found ample to ensure firm adhesion 

 of the section to the slide. The albuminous fluid is prepared 

 as follows: 



FIG. 75. Section rack. 



Mayer's Albumin. 



Weigh out 



Salicylate of soda i gramme 



and dissolve in 



Glycerine 50 c.c. 



Add 



White of egg 50 c.c. 



Mix thoroughly by means of an egg whisk. 



Filter into a clean bottle. 



As an alternative method paint a thin layer of Schallibaum's 

 solution on the slide with a camel's hair pencil; lay the section 

 carefully on this film and heat gently to fix the section. 



