BACTERIOLOGICAL TECHNIQUE 



33 



XXXV. For cutting sections of tissue embedded in celloidin a 

 microtome, with the knife working at an angle, is necessary, and a most 

 serviceable microtome is manufactured by Schanze, Leipzig (see Fig. 9). 



It is important to remember that whatever microtome is used in 

 cutting tissues embedded in celloidin, botht he preparation and knife 

 must be kept continuously wet with alcohol, and the cut sections 



Fin. 9. Schanze's Microtome. 



removed from the knife with a camePs-hair brush, into 60 or 70 per 

 cent, alcohol. The following conditions are absolutely necessary : 



1. A sharp microtome knife. 



2. Hard tissue. 



3. The tissue firmly attached to the block. 



In cutting sections of tissues for the demonstration of bacteria 

 they need not be any thinner than 0'02 mm. 



XXXVI. To stain bacteria in sections, the section is, with few 

 exceptions, always brought directly out of the alcohol into the 

 colouring solution. 



1. Sections remain longer in the dye than cover-glass specimens. 



2. It is often necessary to warm the staining solution either in 



C 



