The principles of bacteriology : a practical manual for students and physicians / by A.C. Abbott.

  • Abbott, A. C. (Alexander Creever), 1860-1935.
Date:
1896
Catalogue details

Licence: Public Domain Mark

Credit: The principles of bacteriology : a practical manual for students and physicians / by A.C. Abbott. Source: Wellcome Collection.

    148/520 (page 144)
    in the preparation were of the same color, but during the application of the decolorizing solution all except the tubercle bacilli gave up their color. This characteristic, together with reactions to be described, as said, serves to differentiate the tubercle bacillus from other organisms with which it might be confounded. A number of different methods have been suggested for the staining of tubercle bacilli, but the original method as employed by Koch is so satisfactory in its results that it is not advisable to substitute others for it. The above differs from the original Koch-Ehrlich method for the staining of tubercle bacilli in sputum only in the occasional em- ployment of Ziehl's carbolic-fuchsin solution and in the method of heating the preparation with the staining fluid upon it. As Nuttall has pointed out, however, the strong acid decolorizer used in this method can, with advantage, be replaced by much more dilute solutions, as a certain number of the bacilli are entirely decolorized by the too energetic action of the strong acids. He recommends the following method of decolorization : After staining the slip or section in the usual way, pass it through three alcohols; it is then to be washed out in a solution com- posed of Water 150 c.o. Alcohol 50 c.e. Concen. sulphuric acid 20 to 30 drops. From this it is removed to water and carefully rinsed. The remaining steps in the process are the same as those given in the other methods. Gabbett's Method for the staining of tubercle bacilli recommends itself because of its simplicity and the rapidity with which it can be performed. By mauy