PLATE-CULTIVATIONS. 69 



also for other purposes, a quantity ready sterilised 

 should always be kept in the box. 



Preparation of Damp Chambers. The damp 

 chambers for the reception of the inoculated plates 

 are prepared thus : Thoroughly cleanse and wash 

 out with (i-iooo) sublimate solution a shallow 

 glass dish and bell (Fig. 7). Cut a piece of filter 

 paper to line the bottom of the glass dish, and 

 moisten it with the same solution. 



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, and three glass rods which have 

 been sterilised by heating in the flame of a Bunsen 

 burner. Provide yourself with a strip of paper or 

 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. 



Method of Inoculating the Test-tubes. 

 Liquefy the gelatine in the three tubes by placing 

 them in a beaker containing water at 30 C., or 

 by gently warming them in the flame of the Bunsen 

 burner. Keep the tubes, both before and after the 

 inoculation, in the warm water, to maintain the 

 gelatine in a state of liquefaction. Hold the tube 

 containing the cultivation and a tube of the 

 liquefied gelatine (to be called the "original") 

 as nearly horizontal as possible between the thumb 

 and index finger of the left hand. With the finger 

 and thumb of the right hand loosen the plugs of 



