Abel's laboratory handbook of bacteriology / [Rudolf Abel].
- Abel, Rudolf Velentine Ludwig, 1868-
- Date:
- [1912?]
Licence: In copyright
Credit: Abel's laboratory handbook of bacteriology / [Rudolf Abel]. Source: Wellcome Collection.
Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.
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![peptone (W) 2, NaCi 1, in water 200. Heat for half an hour in steamer, and, after the fluid has cooled and precipitated, filter. Add to 900 parts of this fluid 100 parts of gelatine, and, after the gelatine has soaked and softened, place in the steamer for, at the outside, half an hour. To the warm solution add 30 parts of a 4% NaOH solution, then add the same drop by drop until blue litmus-paper is no longer reddened by the medium. Heat for quarter of an hour in the steamer, test the reaction, and correct if neces- sary. Add 11 parts of crystallized undecomposed soda, steam for ^-f hour, and Biter. Fill into sterile tubes, 10 c.c. being poured into each, and sterilize these tubes by steaming them once for 15-20 minutes. 3. Maggi's granular bouillon has also been intro- duced as a source of nutrient media by Merck of Darmstadt under the names Ragitbouillon and Ragit- agar powder. From these useful media can be pre- pared by simply boiling and adding definite quantities of soda solution ; special media, e.g. for cholera and typhoid organisms, can also be prepared. [Messrs. Baird & Tatlock and Messrs. Burroughs & Wellcome ■ also supply various media in powder and tablet form which need the addition of water only and boiling.] 4. Neutralization with litmus as indicator is difficult because it is not easy to say when the blue paper no longer becomes red. More exact but more trouble- some is neutralization -wiih.plicnolphtlialein as indicator, which maybe efl'ected as follows: —5 c.c. of the medium is placed in a flask, diluted with 45 c.c. of freshly-pre- pared distilled water, and boiled for three minutes over](https://iiif.wellcomecollection.org/image/b21509645_0034.jp2/full/800%2C/0/default.jpg)
