22 
taking care to use the particular brand of stains 
specified. 
Solution A.—Methylene blue (pure)* ro part 
Sodium carbonate* - 0*5 ,, 
Ordinary water - ioo'o parts 
Keep in the sun, or by the kitchen fire or in a hot 
incubator for two or three days until the solution has 
a distinct purple tinge. The solution is useless until 
this has developed. The solution improves with age 
and exposure to sunlight. 
Solution B.—Eosinf - 1 part 
Water - 1000 parts 
This solution should be kept in a cupboard as it 
becomes gradually decolorised by sunlight. 
For use take 5 c.c. of each stock solution and make 
each up to 100 c.c. with ordinary water. 
To Stain .%—Mix one part of blue and two of the 
eosin solution and pour on the slides. Stain ten 
minutes. Wash in a full stream of water. Blot and 
dry but do not heat. The platelets and nuclei should 
be a deep ruby red without any trace of blue. 
Note 1 .—As it is the precipitate which results from 
the action of the ‘ azure,’etc., on the eosin, which is the 
active staining principle, this mixture must be used 
fresh, at least a few minutes only after making. 
Note II.—While ten minutes or less is quite 
sufficiently long for staining with a good brand of stain, 
yet for certain purposes it may be necessary to stain for 
one or more hours. 
• May be got in soloid form from Burroughs & Wellcome, 
t The eosin is water-soluble, of a yellow shade, or in other words pure eosin for 
blood work, e.g ., the brand known as B.A. It may be got in tabloid form. 
X Mix the solutions in the proportion of i : i, i : 1*5, 1 : 2, etc., and ascertain 
which is the best proportion for each particular brand of stain, e.g., by staining a 
trypanosome, malaria parasite, etc. 
