Measure out and mix

Gentian violet, saturated alcoholic solution 10.0 c.c.
Carbolic acid, 1 per cent. aqueous solution 100.0 c.c.

Filter.

8. _Anilin Water Solution_ (Koch-Ehrlich).

Measure out

Distilled water 100 c.c.

Add anilin oil drop by drop (shaking well after the addition of each
drop) until the solution is opaque.

Filter until clear.

and add

Absolute alcohol 10 c.c.
Saturated alcoholic solution gentian violet 11 c.c.

Filter.

NOTE.--This solution will not keep longer than 14 days.

~Thionine Blue (or Lauth's Violet).~--

9. _Carbolic Thionine Blue_ (Nicolle).

Weigh out

Thionine blue 1.0 gramme
Carbolic acid 2.5 grammes

and dissolve in

Distilled water 100.0 c.c.

Filter.

Before use dilute with equal quantity of distilled water and again
filter.

~Fuchsin (Basic).~--

10. _Saturated Aqueous Solution._

Weigh out

Basic fuchsin 1.5 grammes

and proceed as in preparing the corresponding solution of methylene-blue
(_q. v._).

11. _Saturated Alcoholic Solution._

Weigh out

Basic fuchsin 3.5 grammes

and proceed as in preparing the corresponding solution of
methylene-blue.

12. _Carbolic Fuchsin_ (Ziehl).

Weigh out

Basic fuchsin 1.0 gramme
Carbolic acid 5.0 grammes

dissolve in

Distilled water 100.0 c.c.

and add

Absolute alcohol 10.0 c.c.

Filter.

CONTRAST STAINS.

~Eosin.~--There are several commercial varieties of eosin, which, from the
bacteriological point of view, possess very different values. Gruebler
lists four varieties, of which two only are useful for bacteriological
work:

Eosin, aqueous yellowish.
Eosin, aqueous bluish.

13. _Eosin Aqueous Solution_ (Yellowish or Bluish Shade), 1 per cent.

Weigh out

Eosin, aqueous 1.0 gramme

dissolve in

Distilled water 100.0 c.c.

and add

Absolute alcohol 5.0 c.c.

Filter.

14. _Eosin Alcoholic Solution_, 0.5 per cent.

Weigh out

Eosin, alcoholic 0.5 gramme

and dissolve in

Alcohol (70 per cent.) 100.0 c.c.

Filter.

~Safranine.~--

15. _Aqueous Solution._

Weigh out.

Safranine 0.5 gramme

and dissolve in

Distilled water 100.0 c.c.

Filter.

~Neutral Red.~--

16. _Aqueous Solution._

Weigh out

Neutral red