68 



ESSENTIALS OP BACTERIOLOGY. 



Frankel puts in the test tube, a rubber cork containing two 

 glass tubes, one reaching to the bottom and connected with a 

 hydrogen apparatus, the other very short, both bent at right 

 angles. When the hydrogen has passed through ten to thirty 

 minutes, the short tube is annealed and then the one in connec- 

 tion with the hydrogen bottle, and the gelatine rolled out upon 

 the walls of the tube. (Fig. 40.) Hiippe uses eggs as described 

 in Chapter IX. 



FIG. 39. FIG. 40. FIG. 41. 



w 1 "^ 



Hesse's method. 



Frankel's method. 



Buchner's method. 



Use of JErobic Bacteria to remove the Oxygen. Roux inocu- 

 lates an agar tube through a needle thrust after which semi- 

 solid gelatine is poured in on top. When the gelatine has solidi- 

 fied, the surface is inoculated with a small quantity of bacillus 

 subtilis or some other aerobic germ. The subtilis does not allow 

 the oxygen to pass by, appropriating it to itself. 



