BACTERIOLOGICAL TECHNIQUE 



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culture media, and in all operations concerned with the in- 

 vestigations of micro-organisms, to be able to insure sterility, 



FIG. 4. (a) STERILISER (IN SECTION); (b) WATER-BATH. 



that is, to insure that no organisms are present in, or gain 

 access to, the medium except those which it is intended to 

 study. A culture medium can generally be effectively 



