564 General Notes, 
5. It is then transferred from the preceding to a mixture of equal 
g of oil of origanum and paraffin, which is kept on a water 
ath for an hour or more, at a temperature of 40°C. 
6. It is then transferred to a bath of hard paraffin, or such as 
melts at 55°C., and is kept there until saturation is complete. 
I have tried this method with specimens of injected spleen, and 
find it to work admirably. The sections can be cut with a dry 
knife. The sections form a ribbon more easily than in the case of 
ordinary paraffin imbedding. 
The sections may be freed from paraffin with chloroform before 
mounting if they are required for histological purposes, as they 
may be handled with the greatest ease on account of the presence of 
the celloidin which holds them together. They can then be stain 
in hematoxylin (Kleinenberg’s) or in nigrosin, or double staining 
effects may be produced by the use of other dyes in combination 
with hematoxylin. i 
~ To many persons the oil of origanum has a disagreeable odor, 
and is almost as inflammable as turpentine ; besides, it darkens or 
oxidizes in a short time, and has, I think, a tendency to shrink the 
object slightly, even after treatment with celloidin, and also to 
arken it. 
These disadvantages I have lately avoided by substituting chlo- 
roform for the oil of origanum, used by Dr. Kultschizky. I pro- 
ceed in the same manner as he recommends with the imbed E 
rocess as regards the first, second, and third steps. The fou 
step is to place the object soaked with celloidin in the usual way 
in chloroform until saturated, instead of in oil of origanum. 4t 18 
then transferred to a mixture of paraffin and chloroform, ual 
parts, kept at a temperature of 40°C., and finally, until comp ete 
saturation is effected, in molten hard paraffin melting at 55°C. od 
o clean the sections for mounting, they may be mount 5 
directly from the chloroform, if the operator is quick enough ant 
does not let the chloroform evaporate from the section before it 18 
covered with balsam. A preferable clearing agent, first pro 
by Wiegert, I have found to be a mixture of equal parts of si 
and pure white carbolic acid, which has been allowed to deliqu “a 
or rendered liquid by heat. This may be applied to the oma T 
the slide with a cléan camel’s-hair pencil, and will clean the sec 
instantly without in the least attacking the celloidin. italia 
Serial Sections with Celloidin.'—The celloidin block, te ce 
object imbedded, is cut as regularly as possible, and anit vallel 
cork. In sectioning, the knife should be placed nearly Pe 
with its direction of motion, and after every five to ego he 
wet with 95 per cent. alcohol. The sections are iana yer 
knife with a small brush, and placed on the m pai is 
oil (in a small glass dish over a white ground). aiae 
good the sections will at once unroll and become diel mit 
1 erfertigung längerer Senn ; 
A in aone Aa thee ke 4 Beapel, vii., 4, p. 742, ue 
