l Journal of Jan. 10th, 1880:
PRESERVATION OF OPHTHALMIC SPECIMENS.
Several friends and correspondents have asked me to refer them to a
description of the method which I employ for the preservation of
ophthalmic specimens, examples of which were exhibited in the annual
museum of the Association in Cork last summer. I published an account
of it in the Birmingham Medical Review for July, 1878; but, as several
improvements have been effected since that time, I shall be greatly
obliged by being allowed space in this journal for a brief description
of my present method.
No. 14.--Priestley Smith's Formula.
The following are the solutions, etc, employed:
1. Mueller's Fluid--viz.
Bichromate of potash 1 part,
Sulphate of soda 1 part,
Water 100 parts;
2. Hydrate of chloral and water, 1 in 20;
3. Glycerine and water, 1 in 4,
4. Glycerine and water, 1 in 2--i.e, equal parts;
5. Glycerine-jelly--viz.
Best French gelatine 1 part,
Glycerine 6 parts,
Water 6 parts,
Soak the gelatine in the water until swollen, then heat and add
the glycerine, add a few drops of a saturated solution of carbolic
acid, and filter hot through white blotting-paper;
6. A thick white varnish made by mixing oxide of zinc with copal
varnish in a mortar.
The eyeball is placed, immediately after excision, unopened, in
Mueller's Fluid for about three weeks, light being carefully excluded.
It is then frozen solid by immersion for a few minutes in a mixture of
finely powdered ice and salt, and immediately divided into lateral
halves by means of a sharp-edged table-knife. The portion to be
mounted is then placed in chloral solution for some weeks, in order to
remove the yellow colour; light being still excluded, and the fluid
being changed until it is no longer discoloured by the bichromate. The
specimen next lies for twenty-four hours or longer in the weaker
glycerine solution, and is then transferred for a similar period to
the stronger glycerine solution, after which it may be mounted in the
jelly without danger of shrinking. A specimen-jar being two-thirds
filled with melted jelly, the half-eye is placed in it, the concavity
upwards. When every interstice is filled, it is turned over (care
being taken to avoid the inclusion of an air-bubble), and held in a
central position in contact with the bottom of the jar. When cold and
firmly coagulated, the jelly is coated over with white varnish. A f
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