7O BACTERIOLOGY. 



the tubes. Take the sterilised ose in the right 

 hand and hold it like a pen. Remove the plug 

 from the culture-tube by using the fourth and fifth 

 fingers of the right hand as forceps, and place it 

 between the fourth and fifth fingers of the left. 

 Remove the plug of the " original " in the same way, 

 placing it between the third and fourth fingers of the 

 left hand (Fig. 28). With the ose take up a droplet 



FIG. 28. METHOD OF INOCULATING TEST-TUBES IN THE PREPARATION 

 OF PLATE-CULTIVATIONS. 



of the cultivation and inoculate the ''original," 

 twisting the ose several times in the liquid gelatine. 

 Replace the plugs and set aside the cultivation. 

 Hold the freshly inoculated tube between the fore- 

 finger and thumb of either hand, almost horizontally, 

 then raise it to the vertical, so that the liquid gelatine 

 gently flows back. By repeating this motion and 

 rolling the tube between the fingers and thumbs the 

 micro-organisms which have been introduced are 



