THE USE OF STRONGER STAINING SOLUTIONS. 123 



bacteria will be more fully entered upon later. If, 

 however, we do not know at all what kinds are 

 present, and we wish to examine the section in order 

 to find out, the following method may be employed 

 with advantage. 



I. The sections are treated either with the aqueous 

 or with LofiBer's methylene blue solution, as described 

 in Chapter VIII. If bacteria are present, which resist 

 decolourisation with weak alcohol, they may be exam- 

 ined farther by means of one of the following methods, 

 in order to discover how they are afiiected by other 

 reagents, and to effect a contrast staining. If, on the 

 other hand, the bacteria are unable to resist the de- 

 colourising power of the dilute alcohol, they may 

 generally still be treated by one of the following 

 methods, or, according to Gram's method, by means 

 of which good results are occasionally obtained, and 

 which it is, therefore, best always to use. 



If no bacteria are to be seen, it cannot yet be 

 taken for granted that there are none present in the 

 sections, which must be treated further in the follow- 

 ing manner. 



II. The sections are conveyed most conveniently 

 with a platinum spatula, "^ from the alcohol into the 

 following fluids in the order given : 



' Metal instruments are much more convenient and handy 

 for these purposes than the glass needles and spatulse so 

 frequently recommended, as they are unbreakable, and less 



