A handbook on leprosy.

  • Impey, S. P. (Samuel Patton)
Date:
1896
Catalogue details

Licence: Public Domain Mark

Credit: A handbook on leprosy. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    carbolic acid added to the fuchsine appears to assist the process of staining—probably the acid acts as a mordant. The bacilli may be seen all over the field in countless numbers, some apparently in cells, others free among the corpuscles. When examined under an instrument of high power the stained bacilli sometimes appear to be knotted, there may only be two knots, or there may be more, but usually there are not more than four in a bacillus. Some observers have, I think, erroneously concluded that these knots represent spores. I am of opinion, how- ever, that they are produced in the process of staining by the action of the staining fluid upon the delicate material with which the external membrane of the bacillus is filled. This albuminous matter becomes hardened and contracted, and is thus broken up into two or more parts ; the spaces between the broken parts do not take on the stain, but the albuminous matter does, hence the appearance of knots or spores. Opposite each space the cell-wall also seems to become contracted, so that the appearance presented by tlie stained portion of the bacillus might most readily be mistaken for spores. A bacillus with four knots is equal in length to about half the diameter of a red blood-corpuscle. 2. In the Tissues. (a) Place a properly cut section of a tubercle on a cover glass, put thereon a drojD of acetic acid, and examine with a low-power microscope without staining, and the