first, but gradually becoming deeper.

On the opposite side of the wire make a short cut, 2 mm. in length,
leading from the hole in the same direction. [The use of a fine dental
drill and small circular saw, worked by a dental motor facilitates the
manufacture of these aluminium handled instruments.]

Now pass one end of the platinum wire through the hole, turn up about 2
mm. at right angles and press the short piece into the short cut. Turn
the long end of the wire sharply, also at right angles, and sink it into
the long channel so that it emerges from about the centre of the cut end
of the aluminium wire (Fig. 63). A few sharp taps with a watch maker's
hammer will now close in the sides of the two channels over the wire and
hold it securely.

[Illustration: FIG. 64.--Platinum rod in aluminium handle--method of
mounting.

The platinum wire may be fused into the end of a piece of glass rod, but
such a handle is vastly inferior to aluminium and is not to be
recommended.]

8. Two pairs of sharp-pointed spring forceps (10 cm. long), one of which
must be kept perfectly clean and reserved for handling clean
cover-slips, the other being for use during staining operations.

9. A box of clean 3 by 1 glass slips.

10. A glass capsule with tightly fitting (ground on) glass lid,
containing clean cover-slips in absolute alcohol.

11. One of Faber's "grease pencils" (yellow, red, or blue) for writing
on glass.

12. A wooden rack (Fig. 65) with twelve drop-bottles (Fig. 66) each 60
c.c. capacity, containing

Aniline water.

Gentian violet, saturated alcoholic solution.

Lugol's (Gram's) iodine.

Absolute alcohol.

Methylene-blue, }
Fuchsin, basic, } saturated alcoholic solution.

Neutral red, 1 per cent. aqueous solution.

Leishman's modified Romanowsky stain.

Carbolic acid, 5 per cent. aqueous solution.

Acetic acid, 1 per cent. solution.

Sulphuric acid, 25 per cent. solution.

Xylol.

[Illustration: FIG. 65.--Staining rack, rubber change mat and lysol
pot.]

[Illustration: FIG. 66.--Drop bottle.]

[Illustration: FIG. 67.--Canada balsam pot.]

And two pots with air-tight glass caps (Fig. 67), each provided with a
piece of glass rod and filled respectively with Canada balsam dissolved
in xylol, and sterile vaseline.

METHODS OF EXAMINATION.

Bacteria, etc., are examined microscopically.

1. In the living state, unstained, or stained.
2