GELATINOUS AND ALBUMINOUS INJECTION-MASSES 261
to 350 R., put the preparation to cool on ice as soon as the
operation of injecting is completed, harden in alcohol. Very
delicate objects should be put at once into alcohol previously
cooled by means of ice.
393. Gelatin Injection-mass (Carmine) (Iloyer's formula 1).
-Take a concentrated gelatin solution and add to it a corre-
sponding quantity of the neutral carmine (staining solution)
(Formula No. 58). Digest in a water-bath until the dark
violet-red colour begins to pass into a bright-red tint. Then
add 5-10 per cent. by volumes of glycerin and at least 2 per
cent: by weight of chloral in a concentrated solution. After
passing through flannel, it can be kept in an open vessel under
a bell-glass.
394 Gelatin Injection-mass (Carmine) (Carter's formula 2):
Take-
Carmine       .    .    .     .    1 drachm.
Liq. ammon. fort. .      .    .    2 drachms.
Glacial acetic acid.    .     .    I drachm 26 minims.
Solution of gelatin (1 to 6 of water) 2 ounces.
Water    .    .    .     .    .    1- ounces.
Dissolve the carmine in the ammonia and water; filter if
necessary. Add one ounce and a half of the gelatin solution
hot. Mix the acetic acid with the remaining half ounce of
gelatin, and drop this mixture, little by little, into the carmine
and gelatin solution, stirring briskly all the while.
ti 395 Gelatin Injection-mass (Prussian Blue) (Thiersch's for-
mula -):
Take-
cur.      (1) A solution of I part gelatin in 2 parts water.
ccl bo    (2) A saturated aqueous solution of sulphate of iron.
. 5     (3) A   saturated aqueous solution of red prussiate of
potash.
'Biol. Centralbl.,' ii (1882), pp. 19-22. ' Journ. Roy. Mic. Soc.' (N.S.),
iii (1883), p. 142.   2 Beale,' How to Work, &c.,' 1865, p. 113.
3 ' Arch. Mik. Anat.,' i (1865), p. 148.