Methods of Examination

Bacteria, etc., are examined microscopically.

1. In the living state, unstained, or stained.
2. In the "fixed" condition (i. e., fixed, killed, and stained by suitable methods).

The preparation of a specimen from a tube cultivation for examination by these methods may be described as follows:

1. Living, Unstained.—(a) "Fresh" Preparation.—

1. Clean and dry a 3 by 1 glass slip and place it on one of the squares of filter paper. Deposit a drop of water (preferably distilled) or a drop of 1 per cent. solution of caustic potash, on the centre of the slip, by means of the platinum loop.