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blotting-paper to the edge of the specimen ; this done, two or 
three drops of chloroform should be poured over the section, and 
allowed to remain in contact with it about one minute ; and during 
this time the specimen may be properly arranged in the centre of 
the slide. A slight tilting of the slide then suffices to get rid of 
the chloroform, when, before the specimen becomes dry, two or 
three drops of the solution of Canada balsam in benzole should be 
poured over it from the drop-bottle, and the covering-glass then 
applied. The mounting is thus finished, and the specimen only 
requires a certain amount of protection for a time till the balsam 
in which it is mounted has become hardened. 2nd. The section 
having been placed in the watch-glass with ordinary spirits of wine 
for about a minute (merely to wash it), is then removed to another 
watch-glass or small covered capsule, containing absolute alcohol, 
and allowed to remain in this for five minutes. It is then to be 
removed, and placed on the slide on which it is to be mounted. 
The superfluous alcohol having been got rid of, it is covered with 
one or two drops of benzole for about a minute (which renders 
the section as transparent as if it had been placed in carbolic acid), 
and then, this having been tilted off, the additional steps are as 
before, viz. Canada balsam in benzole from the drop-bottle, followed 
by the application of the covering glass. 
The latter method the author preferred for mounting sections 
of the liver. 
Another method for mounting very delicate tissues consists in 
mounting the specimen in a very weak aqueous solution of bichro- 
mate of potash — about one of the bichromate to 1000 parts of 
water. In using an aqueous medium such as this, however, we 
are placed, as it were, at the mercy of the cement we employ. If 
this be not good, we may, at the time when we most regret it, find 
a valuable specimen ruined, owing to some crack or imperfection 
in the border of cement having permitted the water to evaporate. 
Incomparably the best cement is one which is much used in Ger- 
many, consisting of a solution of gum-mastic in chloroform, thick- 
ened with nitrate of bismuth. This may be easily kept at the 
proper degree of consistence by the addition of a few drops of 
chloroform from time to time. It may be used also for the 
specimens mounted in glycerine and carbolic acid. It does not 
run in, it hardens quickly, and when thoroughly dry has a stone- 
like consistence, and is not liable to crack. 
With regard to mounting sections of brain and spinal cord, 
after speaking of the various substances employed as damaging 
the specimens by atmospheric changes, he stated that the most 
favorable results, independent of atmospheric conditions, might 
be brought about by immersing the section for about ten minutes 
in absolute alsohol diluted with 8 per cent, of water, then placing 
it upon the glass slide, aud before it became dry pouring over it 
two or three drops of pyro-acetic spirit, in which it was allowed to 
remain from — 1'', then tilting this off, and replacing by chloro- 
form. The effects were then watched, as before, under the mi- 
