Prof. Baumgarten has just published in the Ctbl. f. d. Med. Wiss., 25, 1882, the following easy method to detect in the expectorated matter of phthisical persons the pathogenic tubercle bacilli:

Phthisical sputa are dried and made moist with very much diluted potash lye (1 to 2 drops of a 33 per cent. potash lye in a watch glass of distilled water). The tubercle bacilli are then easily recognized with a magnifying power of 400 to 500. By light pressure upon the cover glass the bacilli are easily pressed out of the masses of detritus and secretion. To prevent, however, the possibility of mistaking the tubercle bacilli for other septic bacteria, or vice versa, the following procedure is necessary: After the examination just mentioned, the cover glass is lifted up and the little fluid sticking to its under side allowed to dry, which is done within one or two minutes. Now the cover glass is drawn two or three times rapidly through a gas flame; one drop of a diluted (but not too light) common watery aniline solution (splendid for this purpose is the watery extract of a common aniline ink paper) is placed upon the glass. When now brought under the microscope, all the septic bacteria appear colored intensely blue, while the tubercle bacilli are absolutely colorless, and can be seen as clearly as in the pure potash lye.

We may add, however, that Klebs considers his own method preferable.

As the whole procedure does not take longer than ten minutes, it is to be recommended in general practice. The consequences of Koch's important discovery become daily more apparent, and their application more practicable.

[Concluded from SUPPLEMENT No. 384, page 6132.]