1887.] MICROSCOPICAL JOURNAL. 165 
The method of using myrtle wax is as follows :—The specimens are dehy- 
drated in absolute alcohol and then placed in a solution of wax in chloroform, 
as a preliminary bath, or transferred directly to the melted wax. The pieces 
will be infiltrated in about the same time required by the paraffine method. 
The pieces may be fastened on cork, by using the melted wax, or imbedded 
in blocks of wax or paraffine, to support the specimen in the clamp of the 
microtome. 
The sections are cut dry, into benzole, washed in alcohol, stained and 
mounted as usual. 
To completely remove the wax it is best to take the sections through a 
second bath of benzole, as any remaining wax will be precipitated by the 
alcohol used in the washing. 
Warm absolute alcohol may be used to free the sections from wax, but the 
benzole is better and cheaper. 
Ordinary alcohol warmed will not dissolve the wax perfectly ; warmed ab- 
solute alcohol will dissolve most of it, but will deposit it on cooling; I, there- 
fore, think that the above method is preferable to the immediate transferring 
from the preserving alcohol to the wax bath, as advised by Dr. Miller. 
The method is more rapid than either the paraffine or celloidin process ; 
there is very little if any shrinkage ; it does not injure the most delicate tissues, 
and it is inexpensive. 
The specimens I exhibit show the comparative shrinkage by this and by 
the Reeves Method. 
If hardened in large masses there is a s/7gh¢ shrinkage and a tendency to 
crack; this, I think, may be prevented by the addition of a small amount of 
paraffine with which it is miscible in all proportions. 
I never have seen a section injured by cracking. 
WAX METHOD APPLIED TO THE PREPARATION OF BRAINS FOR ANATOMICAL 
DEMONSTRATION. 
The specimens of brains I exhibit were prepared by the use of myrtle wax 
as an infiltrating agent. The process is as follows :— 
To prevent shrinkage the brain should be carefully hardened in a solution 
of one of the chromic acid salts, after which it should be gradually advanced 
through alcohols increasing in strength until absolute alcohol is reached. 
It should be dehydrated and then either placed in an intermediate bath of 
wax dissolved in chloroform, or at once into the melted wax. About three 
days are required to infiltrate a hemisphere. 
The dark olive color produced by the hardening fluid is the only objection 
to this method. By the use of other hardening agents a more pleasing color 
may be obtained, but the shaf~e and szze of the specimen are perfectly pre- 
served by hardening in Miller’s fluid and myrtle wax infiltration. 
The light colored specimens were hardened in alcohol; but the shrinking 
and distortion produced by this agent are objections to this. 
A very fair degree of success may be attained by a direct transfer from the 
alcohol, used to preserve the brain, to the melted wax. In fact, some of the 
brains I exhibit were done in this way; but the wax must be heated toa 
much higher degree than would be safe for microscopical preparations. 
Dr. Dwight, in the Boston Med. and Surgical Journal, Mar. to, 1887, 
describes Schwalbe’s methods for making preparations of brain for demon- 
stration, by the use of paraffine; but he says it is ‘ apparently applicable to 
parts of brain rather than the whole organ.’ I have tried the Schwalbe 
method, but with less satisfactory results than with the wax method, which, 
so far as I know, is a new process. 
