BACTERIOLOGICAL TECHNIC 25 



The basket which is to receive the tubes after filling 

 should be placed in an inclined position, as this facili- 

 tates the proper arrangement of the tubes. In filling 

 the tubes the pipette at the end of the rubber hose 



FIG. 14 

 Filtering Media by Means of Vacuum Pump 



a. Liquid medium e. Reflux flask 



b. Absorbent cotton /. Rubber stopper with two holes 



c. Rubber stopper g. Connection with aspirator 



d. Filtered medium 



should be inserted to a depth of at least two inches 

 and when the proper amount has been discharged 

 should be removed carefully so as to avoid wetting 

 the mouth of the tube. A wet tube-mouth will cause 



