THE MICROSCOPE. : 19 
and the sterilization of instruments, etc., should receive careful atten- 
tion. After the incisions have been made, the various fluids of the 
body are to be sterilized by plunging a platinum wire into them, and 
portions then placed in culture tubes or on plates which have been pre- 
viously prepared. Tissues to be investigated are burned over with a 
hot glass rod, the part beneath removed, and a piece for examination 
taken from this by means of a red-hot platinum wire. By 
inoculation of these various materials thus obtained, Babes is of the 
opinion that it may be possible to discover, among other things, why . 
the course of infectious diseases in man is so variable in different 
‘individuals. 
Preparations For Hien Powers.*—J. W. Gifford finds, that 
where a very faithful and instant fixing of the tissue elements is 
required, a slight modification of Fleming’s chrom-acetic-osmic acid 
is the best agent to employ. On account of the very feeble powers 
of penetration possessed by this agent, the material must be cut 
into small pieces before immersing. ‘The fluid employed is made as 
follows: To a watch-glass of § per cent. chromic acid solution, 
made with distilled water, sufficient osmic acid is added to make it 
smell distinctly, and finally one drop of formic acid. The fresh 
material is placed in this from $ to 2 hours—penetration being 
hastened by slightly warming the fluid—washed in several changes 
of water, containing a little glycerine, and stained in a mixture of 
equal parts of Kleinenberg’s hematoxylin and glycerine. The stain- 
ing process should go on for two days, after which the specimen is 
placed in equal parts of glycerine and water, and kept at a luke- 
warm temperature for a week or longer, until most of the water is 
evaporated. It may then be mounted whole, or sectioned and 
mounted in glycerine jelly, the formula for which is : 
Giycerine Reso ete Roe ate Oats 150 grammes. 
ST MOEASHER s Se toa cle ioe een a) ae 30 a 
MERE eine. 2 west als: id dns ote ede erg rans at, q. 5. 
Dissolve the isinglass in a very little water, clarify with white 
of egg, strain through muslin, add the glycerine, and keep the whole 
for some days at about 60° C., until the greater part of the water 
has evaporated. In this way a very highly refracting jelly may be 
made. 
* Allen’s Jour. of Microscopy. July, 1888. 
