234 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
The knob h , with the wheels a and c , constitute the fine adjustment. The 
knob h indicates whole or half mikrons, and another screw b unites the 
wheel a with the micrometer-screw. The connection between the two 
wheels a and c can be raised, and the latter afterwards depressed; the 
screw i serves for fixing it. Photographs of some of the sections ob- 
tained accompany the description. 
Rapid Method of Paraffin Imbedding.* — Dr. S. H. Champlin’s 
method is as follows. A piece of fresh tissue the thickness of a thin or 
medium slide is suspended in absolute alcohol from 2-2J hours. It is 
then placed in benzol-cedarwood oil mixture until semi-transparent 
(usually from 10-30 minutes). It is next immersed in melted paraffin 
heated to between 47° and 50° C. This paraffin is a mixture of one part 
hard paraffin (50° C.) and two parts soft paraffin (40° C.) After the 
bath, which takes from 5-30 minutes, the specimen is imbedded in 
melted paraffin (two parts hard and one part soft paraffin) and allowed 
to cool slowly until semi-solid, when it should be rapidly cooled in ice 
water. The sections are fixed to the slide with Mayer’s albumen mix- 
ture ; passed through benzine and 90 per cent, alcohol ; stained with 
China blue or bleu de Lyon, and afterwards with safranin ; and mounted 
in balsam. 
The safranin solution is made by adding 1 part of 40 per cent, forma- 
lin to 4 parts of saturated aqueous solution of safranin. 
The entire process can be carried out in 3J-4 hours. 
(4) Staining 1 and Injecting. 
Three Staining and Mounting Methods. j — Elise Wolff gives the 
following modification of Weigert’s fibrin and bacteria method. (1) The 
alcoholic solution of gentian-violet is mixed with a saturated aqueous 
solution of lithium carbonate instead of with anilin-water. The solu- 
tion must be made fresh when required for use. For staining fibrin, 
two thirds of lithium carbonate solution and one-third gentian-violet 
solution are required. In this the preparations are immersed for 3 or 
4 minutes, and then in the iodine solution for 1-IJ minutes. They arc 
decolorised first in pure anilin and afterwards in anilin-xylol (2-1). 
The preparations are extremely permanent. For bacteria, one-third 
lithium carbonate solution and two-thirds staining solution are required. 
In this the preparations are stained 5 or 6 minutes, or longer. 
Instead of gentian-violet, a saturated alcoholic solution of fuchsin 
may be used, but the staining time must be extended to quite 10 minutes. 
The authoress is accustomed to celloidin sections which are stuck on 
by Aubertin’s method .J 
(2) A good nuclear staining for material hardened in Muller’s fluid 
or Benda’s solution (nitric-acid-bichromate of potash solution) is obtained 
by immersing the sections for 24 hours in very dilute Bohmer’s haemato- 
xylin. After this the sections (if the materials have been hardened in 
Muller) are immersed in another quantity of the same haematoxylin 
solution, to which so much 5 per cent, aqueous solution of oxalic acid 
* Journ. Applied Microscopy, ii. (1899) pp. 229-30. 
f Zeitschr. f. wiss. Mikr., xv. (1899) pp. 310-2. 
% Cf. this Journal, 1897, p. 174. 
