IODINE-GREEN

CHAPTER XIV.
I IODINE- AND METHYL-GREEN, ANILIN-BLUE, QUINOLIN, IN-
DULIN, METHYL-VIOLET, SAFRANIN, BISMARCK BROWN,
EOSIN, BENGALE ROSE.
139. Iodine-Green     ("Hoffmann's Grin") (Griesbach's
i method1).-odine-green, or Hoffman's green, is the hydriodide
i of tetramethylrosanilinmethyliodide. As to the chemistry of
I the substance, see Hofmann and Girard ' Ber. chem. Ges.,' ii,
440, Hofmann, ibid, vi, 552, and Hofmann, ' Monatsbericht
i der Kbnigl. Academie der Wiss. zu Berlin,' 15th July, 1869.
Griesbach employs the following solution:
Crystallised iodine-green    .    .      01 gr.
Distilled water    .    ,    .    .     350 ,,
These proportions may be varied according to the desire of
the operator, within limits indicated only by the observation
that good results can only be obtained from deep-hued solu-
tions.
The objects are to be put into water for a few seconds
before staining. They stain instantaneously in general.
They are to be washed out in water, and brought into glyce-
rin, or dehydrated in absolute alcohol and passed through
oil of cloves or anise-seed into balsam or dammar. The stain
is not destroyed by immersion in alcohol for days. The pre-
parations are apparently permanent in balsam.
Alcoholic solutions may be used for staining, but Griesbach
finds no advantage in so doing.
A nuclear but frequently diffuse stain, valuable for the
exceeding rapidity of its action, and for its striking power
I ' Zool. Anz.,' No. 117 (vol. 5, 1882), p. 406.

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