ANAEROBIC CULTURES 241 



2. Place a tablet of pyrogallic acid in one division 

 of the interior of the plate base, and two tablets of 

 sodic hydroxide in the other. 



3. Prepare surface plate culture of the organism to 

 be cultivated. 



4. Run a few cubic centimetres of distilled water 

 into that division of the plate base containing the 

 sodic hydroxide. 



5. Invert the bottom half of the surface plate over 

 the plate base and press its edges firmly down into the 

 plasticine filling the groove. 



6. Label and incubate. 



(D) Method IX.- 



Apparatus Required. 



Small Ruffer's or Woodhead's flask (Fig. 33). 



Sterile india-rubber stopper. 



India-rubber tubing. 



Glass tubing. 



Metal screw clips. 



Cylinder of compressed hydrogen ; or hydrogen gas apparatus 



METHOD. 



1. Sterilise a glass vessel, shaped as in a Ruffer's or 

 Woodhead's flask, in the hot-air oven. (The tubulure 

 and the side tubes are plugged with cotton- wool.) 

 After sterilisation, fix a short piece of rubber tubing 

 occluded by a metal clip to each side tube. 



2. Inoculate a large quantity (e. g., 200 c.c.) of the 

 medium. Where solid media are employed they must 

 first be liquefied by heat. 



3. Remove the cotton-wool plug from the tubulure 

 and pour the inoculated medium into the glass vessel. 



4. Close the tubulure by means of an india-rubber 

 stopper previously sterilised by boiling in a beaker of 

 water. 



5. Connect up the india-rubber tubing on one of 

 the side tubes with a cylinder of compressed hydrogen 



16 



