210 MICROSCOPIC AND CULTURAL STUDY OF BACTERIA 



The "bottle-plate" method of Simonds and Kendall 1 overcomes this 

 difficulty to a considerable degree through the use of simple appli- 

 ances. 



Sixteen-ounce French square tincture-mouth bottles are plugged 

 with cotton and sterilized with dry heat. With the bottles lying on 

 their sides, sufficient blood agar is poured in to form a layer 5 to 10 



mm. deep, and allowed to harden. Dorset's 

 egg medium, dextrose agar or other media 

 may be substituted for the blood agar if 

 desired. 



As soon as the medium has hardened the 

 bottles should be turned on the opposite 

 side, thus bringing the medium uppermost 

 and preventing condensation water from 

 adhering to it. Inoculation is made with a 

 bent glass rod infected with bacteria from 

 a thin suspension in a liquid medium, and 

 rubbed over the surface of the agar within 

 the bottle. A partial vacuum is next cre- 

 ated within the bottle, and residual oxygen 

 dissolved in alkaline pyrogallate solution 

 in the following manner: A closely fitting 

 rubber stopper with one hole carrying a 

 glass tube four inches in length is inserted 

 in the bottle. The outer end of the glass 

 tube projects three-quarters of an inch 

 beyond the stopper and is fitted with a 

 rubber tube three inches in length. That 

 portion of the glass rod within the bottle 

 ^ bent at an angle of 45 and the stopper 

 is turned in such a manner that the end of 

 the glass tube points toward the side of the 

 bottle opposite the layer of agar. As much 



air as possible is aspirated from the bottle, and the rubber tube 

 closed with a pinch-cock to prevent reentrance of air. 



The bottle is now placed on its side, with the medium uppermost, 

 and with a pipette, 10 c.c. each of a 50 per cent, solution of pyrogallic 

 acid and 10 per cent, sodium hydrate are run in through the rubber 

 tube, avoiding the entrance of air. A few cubic centimeters of clean 



1 Jour. Inf. Dis., 1912, xi, 207. 



FIG. 25. Wright's method of 

 making anaerobic cultures in 

 fluid media. (Mallory and 

 Wright.) 



