little finger and the palm of the right hand (whilst still
holding the loop as directed in step 4), and remove it from
the mouth of the tube by a "screwing" motion of the right
hand.

6. Introduce the platinum loop into the tube and hold it in
this position until satisfied that it is quite cool. (The
cooling may be hastened by touching the loop on one of the
drops of moisture which are usually to be found condensed on
the interior of the glass tube, or by dipping it into the
condensation water at the bottom; at the same time care must
be taken in the case of cultures on solid media to avoid
touching either the medium or the growth.)

7. Remove a small portion of the growth by taking up a drop
of liquid, in the case of a fluid culture, in the loop; or
by touching the loop on the surface of the growth when the
culture is on solid medium; and withdraw the loop from the
tube without again touching the medium or the glass sides of
the tube.

8. Replace the cotton-wool plug in the mouth of the tube.

9. Replace the tube cultivation in its rack or jar.

10. Mix the contents of the loop thoroughly with the drop of water on
the 3 by 1 slide.

11. Again sterilise the loop as directed in step 4, and replace it in
its stand.

12. Remove a cover-slip from the glass capsule by means of the
cover-slip forceps, rest it for a moment on its edge, on a piece of
filter paper to remove the excess of alcohol, then pass it through the
flame of the Bunsen burner. This burns off the remainder of the alcohol,
and the cover-slip so "flamed" is now clean, dry, and sterile.

13. Lower the cover-slip, still held in the forceps, on to the surface
of the drop of fluid on the 3 by 1 slip, carefully and gently, to avoid
the inclusion of air bubbles.

14. Examine microscopically (_vide infra_).

During the microscopical examination, stains and other reagents may be
run in under a cover-slip by the simple method of placing a drop of the
reagent in contact with one edge of the cover-glass and applying the
torn edge of a piece of blotting paper to the opposite side. The reagent
may then be observed to flow across the field and come into contact with
such of the micro-organisms as lie in its path.

The non-toxic basic dyes most generally employed for the intra-vitam
staining of bacteria are

Neutral red, }
Quinoleine blue }
Methyl