BACTERIOLOGICAL APPARATUS 



55 



bacteria one needs aniline dyes, such as basic fuchsin, 

 methyl en e blue and others, together with small bottles and 



Fig. 16. Bottles for holding balsam and reagent. 



droppers to contain the properly prepared solutions of these 

 dyes. 



Apparatus needed for making culture media and isolat- 

 ing bacteria. For these purposes a large variety of test 



tubes and flasks is {employed. 

 For the ordinary 'work, culture 

 media can be conveniently 

 stored in Erlenmeyer flasks of 

 500 cc. capacity. Larger or 

 smaller ones may be used if 

 desired. For many cultures 

 the media are distributed in 

 small and larger test tubes. 

 There is a considerable variety 

 of tubes used for this purpose. 

 The ordinary test tubes, from 

 8 to 12 mm. in diameter and 

 from 10 to 15 cm. in length, are 

 quite commonly employed. A 

 tube known as the "Board of 

 Health" tube which is made of 

 heavier glass about 8 mm. in 

 diameter and 12 cm. in length and is ^without a lip is found 



Fig. 17. Large and smaller 

 test tubes for culture media. 

 The middle size is used most 

 for cultures, the largest for 

 storing media for plate cul- 

 tures, and the smallest for 

 serum agglutination work. 



