DIPHTHERIA. 47 
mouth, taking great care not to touch his lips, tongue, 
or palate. Press it firmly against the area which you 
wish to examine and rotate it between the finger and 
thumb so as to remove some of the secretion, and, if 
possible, some of the membrane. Withdraw the swab, 
again taking care not to touch any part of the mouth, 
and replace it in the tube. 
5. Withdraw the tongue depressor and place it in the 
antiseptic lotion or boiling water. 
‘ 6. Push the cork home into the tube. 
Method of examining the swab. 
This may be carried out by means of stained films 
prepared directly from the swabs, or by means of cul- 
tures. The former method is less useful that the latter, 
but we shall consider it first, as it can be performed by 
anyone who: possesses a microscope carrying a jy in. 
oil immersion lens, and often gives valuable informa- 
tion. Moreover, it does not, take long and but little 
delay is caused. 
Requisites.—1. ‘Clean slides and cover-glasses. 
2. Stains—Lé6ffler’s blue or carbol-thionin, and aniline 
gentian violet. 
3. Gram’s iodine solution and alcohol—methylated 
spirit will do. 
4. Strips of white filter- or blotting-paper. 
5. Balsam. 
Method.—Prepare a film in the following way:—Rub 
the swab on the middle of a clean slide so as to spread 
some of the secretion into a thin layer on the surface. 
Allow it to dry, and fix it by passing it slowly through 
the flame until the upper surface is just too hot to 
prevent your pressing your finger upon it in comfort. 
Allow it to cool. 
Now filter a few drops of Léffler’s blue or carbol- 
