210 



BACTERIOLOGY 



into a larger tube, in the bottom of which have been deposited 

 1 gram of pyrogallic acid and 10 e.e. of to normal caustic- 

 potash solution. The larger tube is then tightly plugged 

 with a rubber stopper. The oxygen is quickly absorbed 

 by the pyrogallic acid, and the organisms develop in the 



Fig. 38 



'J) 



Frankel's method for the cultivation of anaerobic bacteria. 



remaining constituents of the atmosphere, viz., nitrogen, a 

 small amount of CO2, and a trace of ammonia. 



Method of C. Frankel. Carl Frankel suggested the fol- 

 lowing: the tube is first inoculated as if it were to be poured 

 as a plate or rolled as an ordinary Esmarch tube. The cotton 

 plug is then replaced by a rubber stopper, through which 



