. The principles of bacteriology: a practical manual for students and physicians. allowed to solidify. Itis, therefore, necessary that the plates should not onlybe sterile when placed upon the stages, but that duringmanipulation they should be carefully protected by acover against dust and bacteria from without. 134 BACTERIOLOGY. A number of plates at a time are usually sterilized inthe dry sterilizer at a temperature of 150° to 180° one hour. During sterilization and until usedthey are retained in an iron box (Fig. 25), which isespecially designed for the purpose. They should neverbe pl
. The principles of bacteriology: a practical manual for students and physicians. allowed to solidify. Itis, therefore, necessary that the plates should not onlybe sterile when placed upon the stages, but that duringmanipulation they should be carefully protected by acover against dust and bacteria from without. 134 BACTERIOLOGY. A number of plates at a time are usually sterilized inthe dry sterilizer at a temperature of 150° to 180° one hour. During sterilization and until usedthey are retained in an iron box (Fig. 25), which isespecially designed for the purpose. They should neverbe placed upon the stage until cold; otherwise theycrack. When the plates which have been placed upon thestages are quite cold the melted gelatin or agar-agar inthe tubes which represent the three dilutions should bepoured upon them, each tube being emptied upon aseparate plate. If the medium is quite fluid, it spreadsover the surface of the plates in a thin, even it may be more evenly spread as it flowsfrom the tube by the aid of a sterilized glass rod. Fig. Glass benches for supporting plates. As the content of each tube is emptied the cover ofthe cooling-stage is quickly replaced and the plate al-lowed to stand until the gelatin or agar-agar is quitesolid. This takes longer with gelatin than with the medium is quite solid these plates are placedupon glass benches (Fig. 26), each labelled with the num-ber of the plate in the series of dilutions. The benches,with the plates upon them, are then piled one above theother in a culture-dish, in which the plates are to bekept during the growth of the bacteria. The benches CULTURE-DISH. 135 are sterilized before using, in the same manner asplates. Culture-dish.—This dish, which is about 22 diameter and has vertical sides about 6 cm. in height,is provided with a cover of exactly the same shape,but of a little larger diameter. This cover, whenplaced upon the dish containing the plates, preventsthe ac
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectbacteri, bookyear1902
