INOCULATION OF CULTURE MEDIA. 23 



3. A Bunsen's burner or a spirit lamp with a tall 

 flame. 



4. A pair of dissecting forceps. 



5. Platinum needles. Each needle consists of a piece 

 of platinum wire about three inches long mounted in 

 the axis of a glass rod about six or eight inches in 

 length. The wire should be just thick enough not to 

 bend too easily. They are easily prepared. The rod 

 is selected and the length of platinum wire is held in an 

 ordinary pair of forceps. The end of the glass rod is 

 held in the flame until quite soft ; the end of the wire is 

 then heated to redness, and pushed into the rod to the 

 depth of about a quarter of an inch, taking care that it is 



FIG. 9. 



kept in the axis. The whole is allowed to cool and is 

 ready for use. 



For some purposes we use needles which terminate 

 in a small loop, so that they will retain a drop of fluid. 

 These are prepared in the same way as the straight 

 needles, the free end of the wire being subsequently 

 twisted round a French nail or other suitable object. 



The method is as follows : 



i. Hold the culture tube you are going to inoculate 

 first between the index and middle fingers of the left 



