THE MICROTOMIST S VADE-MECUM

1-525 if desired, by evaporating the solution somewhat, or by
adding more carbolate.
343. Glycerin and Alcohol Mixture (Hdntsch's fluid').

Alcohol.     .     .
Glycerin     .    .
Water .      .    .
The proportions of this     mixture may
varied with advantage.    I have found the
useful:
344.   Alcohol     .    .
Glycerin    .    .
Water       .    .
as well as fluids weaker in alcohol and glyceri
345.   Alcohol     .    .
Glycerin    .    .
Water       .    .
346. Dilute Alcohol (Carpenter's formula 2).

3 parts.
1
2
frequently be
following very
1 part.
1 ,,
1 ,,
a, down to-
1 part.
1 ,,
3

Alcohol        .    .    .       .    1 part
Water       .    .     .    .    .    5
347. Biniodide of Mercury      and  Iodide of Potassium
(Stephenson's formula 3).-A solution of the two salts in
water. ".This is very easily prepared by adding the two
salts to the water until each shall be in excess; when this
point of saturation has been reached the liquid will be found
to have a refractive index of 1-68, by far the highest aqueous
solution known to me. Its advantages from an optical point
of view are considerable, and it may be used of any strength;
commencing with pure water, with a refractive index of 1-33,
we can go on progressively to 1-465, which represents gly-
cerin, still on to 1-54 (Canada balsam), again onwards to
1P624, which represents bisulphide of carbon, to 1-658, which
represents the monobromide of naphthalin, to 1-662, the
' Micro. Dict.,' Art. " Preservation."
2 The Microscope,' p. 246.
' Journ. Roy. Mic. Soc.,' (N.S.), ii (1882), p. 167.

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