82 BACTERIOLOGY. 



"oese" as it is called, Fig. 10. This is nothing more than 

 a piece of platinum wire of about 5 c.m. long, twisted into 

 a small loop at one end and fused into a bit of glass rod, 

 which acts as a handle, at the other extremity. This 

 a oese" is one of the most useful of bacteriological instru- 

 ments, as there is hardly a manipulation in the work into 

 which it does not enter. Under no conditions is it to be 



FIG. 10. 



employed without having been passed through the gas- 

 flame until quite hot ; this is for the purpose of sterili- 

 zation. One should form a habit of never taking up 

 one of these "oeses," or platinum- wire needles, as they 

 are also called, for they are both looped and curved or 

 straight, without passing it through the flame, and the 

 sooner the beginner learns to do this as a matter of 

 reflex, the sooner does he rid himself of one of the pos- 

 sible sources of error in his work. It must be remem- 

 bered, though, that the " oese " should not be used when 

 hot, otherwise the organisms taken up with it are killed 

 by the high temperature; after sterilizing it in the flame 

 one waits for a few seconds before using it. 



The bit of material under consideration is transferred 

 with the sterilized " oese " into tube No. 1, "the 

 original," where it is carefully disintegrated by gently 

 rubbing it against the sides of the tube. The more 

 carefully this is done the more homogeneous will be the 



