CHAPTER V 



METHODS OF INOCULATION 



Having now in test-tubes and small flasks sterile material 

 ready for inoculation, it is necessary to describe the mode 

 of inoculating the same. 



I. Inoculations from Artificial Cultures. — The first and 

 simplest is the case where it is required to inoculate a new 

 tube or flask with a definite organism that has been growing 

 previously in a culture tube ; that is to say, where it is 

 required to establish from an artificial cultivation a new 

 subculture. Take a freshly drawn-out capillary pipette, 

 with a fine point, as described in a former chapter ; draw 

 up with sterile forceps shghtly the top part of the cotton- 

 wool plug of the old tube or flask, push carefully and gently 

 one of the pointed ends of the capillary pipette — the other 

 can be broken off blunt — through the remaining part of the 

 cotton-wool plug, and push it downwards till it emerges 

 into the culture-fluid, or, if this be solid material, till it 

 reaches the spot or place where the organism is growing ; 

 allow a small droplet to ascend into the capillary pipette, 

 which it readily does by capillarity ; or if a larger quantity 

 is required draw it up by gently sucking at the outer end of 

 the capillary pipette. Then draw the capillary pipette 



