ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
487 
Demonstrating the Tubercle Bacillus in the Sputum.* — M. J. 
Amann gives the result of a 12 years’ experience of examining for 
tubercle bacilli in the sputum. All the sputum should be tested, and 
it is made homogeneous either by squeezing it between two ground-glass 
plates or by sedimentation. The former method requires no explanation ; 
with regard to sedimentation, the author points out that any chemical or 
physical means which are detrimental to the tinctorial properties of the 
bacilli should never be adopted, and his method for treating the mass 
is to place it in a glass vessel holding about 100 ccm. 2-4 volumes of 
distilled water are then poured over it so that the vessel is about half full. 
1 ccm. of chloroform and some clean lead shot are then put in, and the 
vessel having been tightly plugged is shaken up for some minutes. The 
fluid is then placed in a conical wine-glass, or better still in a U-shaped 
glass tube, the bottom of which is narrowed to 2 mm., so that it resembles 
somewhat a Geissler’s burette. 2 ccm. of phenol-fuchsin solution are 
then added and the apparatus shaken. The top is closed with a 
perforated caoutchouc plug, through the aperture of which is inserted a 
balloon syringe. After standing for 24-48 hours the sediment will 
have deposited, the supernatant fluid being quite clear. The bulb is 
then squeezed and the sediment flows out into a receptacle placed to 
receive it. The sediment can then be examined for epithelium or elastic 
fibres as well as for bacilli. The sedimentary sputum is next spread on 
slides, and when dry fixed either by heat or by immersion in equal 
volumes of ether and absolute alcohol, the latter process being preferred 
as it removes the fatty particles. 
For staining the preparations (already partially coloured) use phenol- 
fuchsin 1 grm., fuchsin 5 grm., 90 per cent, carbolic acid, and 95 ccm. 
hot distilled water. A few drops of this solution are poured on the slide, 
which is then heated till it vaporises over a spirit-lamp. The prepara- 
tion is decolorised as follows : — It is first treated with 20 per cent, 
picro-sulphuric acid for 1/2-1 minute and then washed thoroughly in 
running water. It is next treated with the special solution, 15 grm. 
fluorescein, 15 grm. methylen-blue, 500 ccm. absolute alcohol, until 
the sputum is of a pale greenish-yellow colour. The next step is to 
stain the preparation with malachite-green in dilute aqueous solution, 
and this done it is dried at a temperature of 60-80°. While it is still 
warm cedar oil is dropped over one or two spots, and when cold the 
preparation is examined without the interposition of a cover-glass, though 
of course it can be mounted in the usual way. 
(3) Cutting-, including- Imbedding- and Microtomes. 
Microtome for Cutting Sections under Spirit. — Alexander Bruce, 
M.D., F.K.C.P.E., Lecturer on Pathology, Surgeons’ Hall, Edinburgh, 
writes : — Most microscopists who have had occasion to use a sliding 
microtome to cut sections from tissues imbedded in celloidin have been 
met by several difficulties in their work. Among them may be men- 
tioned : — (1) Friction of the cut section against the blade. This is 
obviated fairly well in the case of small sections by dropping spirit 
on the blade ; but when the sections are of considerable size it is very 
* Centralbl. f. Bakteriol. u. Parasitenk., l te Abt., xvii. (1895) pp. 513-22. 
