. A text-book of bacteriology, including the etiology and prevention of infective diseases and a short account of yeasts, and moulds, haematazoa, and psorosperms. Bacteriology. NUTRIENT MEDIA AND METHODS OF CULTIVATION. 121 a long filament, and the subsequent development of brigiit oval spores. It is necessary carefully to observe the minutest details in order to maintain the cultivation pure. An excavated shde is thoroughly cleaned, and then sterilised by being held with the cupped side downwards in the flame of the Bunsen burner. A ring of vaseline is painted round the excavation, and the sl
. A text-book of bacteriology, including the etiology and prevention of infective diseases and a short account of yeasts, and moulds, haematazoa, and psorosperms. Bacteriology. NUTRIENT MEDIA AND METHODS OF CULTIVATION. 121 a long filament, and the subsequent development of brigiit oval spores. It is necessary carefully to observe the minutest details in order to maintain the cultivation pure. An excavated shde is thoroughly cleaned, and then sterilised by being held with the cupped side downwards in the flame of the Bunsen burner. A ring of vaseline is painted round the excavation, and the slide is then placed under a glass bell. Meanwhile a carefully cleansed cover- glass is also sterilised by passing it through the flame, and should be deposited on a sterilised glass plate. With a sterihsed looped needle, a drop of sterile broth is transferred to the cover-glass, and this is inoculated by touching it with another sterilised needle charged with the material to be examined, without disturbing the form of the drop. It is quite suflicient just to touch the drop. .-3 Fig. 48.—Deop Cultivation. (a) Drop of broth ; (b) layer of vaseline. instead of transferring a \'isible quantity of blood, juice, or growth, as the case may be. The slide is then inverted and placed over the cover-glass, so that the drop will come exactly in the centre of the excavation, and is gently pressed down. On turning the shde over again the cover-glass adheres, and an additional layer of vaseline is painted round the edges of the cover-glass itself. The slide must be labelled, and if necessary, placed in the incubator, and the results watched from time to time. Instead of broth, liquid blood serum may be employed in this form of cultivation. If it is required to preserve the drop-cultivation as a microscopic preparation, the cover-glass is gently lifted off and allowed to dry. Any vaseline adhering to the cover-glass should be wiped off, and the cover-glass can then be passed through the flame
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Keywords: ., bookcentury1800, bookdecade1890, bookpublisherphila, bookyear1897
