108 



BACTERIOLOGi'. 



cleanse and wash out with Tin 20 carbolic acid a shallow glass dish 

 and bell. Cut a piece of filter-paper to line the bottom of the glass 

 dish, and moisten it with the same solution. 

 Metliod of Inoculating the Test-tubes. — In 

 a glass beaker or an ordinary glass tumbler, 

 with a pad of cotton-wool at the bottom, 

 place the tube containing the cultivation, 

 the three tubes to be inoculated, three glass 

 rods which have been sterilised by heating 

 in the flame of a Bunsen burner, and a 

 thermometer. Provide a strip of paper, a 

 large label, a pencil, a pair of forceps, and 

 inoculating needles. All is now ready at 

 hand to commence the inoculation of the tubes. 

 Lifpiefy the gelatine in the three tubes b}' placing them in a 

 beaker containing watei' at 30° C, or by gently warming them in 

 the flame of the Bunsen })urner. Keejp the tubes, both before and 

 ;ifter the inoculation, in the warm water, to maintain the gelatine 

 in a state of liquefaction. Hold the tube containing the cultivation 



Fig. 37.— Iron Bo.\ 

 Gl.'Iks Plates. 



Fig. 38.— Method of Inoculating Test-tubes in the Pkepakation 

 OF Plate-cultivations. 



and a tube of the liquefied gelatine as nearly horizontal as possible 

 between the thumb and index finger of the left hand. With the index 

 finger and thumb of the right hand loosen the plugs of the tubes. 

 Take the looped platinum needle 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 



