146 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
are in some respects not suited to modern requirements. We have 
therefore ceased to make such, and have replaced them by new instru- 
ments, which we shall hereafter class under the head of microtomes. 
The instrument presented here is dissimilar from the Laboratory 
and Student microtomes of our manufacture in not having mechanical 
movement for the knife ; it is intended to be fastened to the table-top 
by means of thumb-screw. The cutting-plate of the instrument is inlaid 
with glass to obtain perfect smoothness. To the carriage are directly 
fitted the micrometer-screw with graduated disc, and a section-clamp 
which is acted upon by the former. The pitch of the screw is 1/50 in., 
graduation on disc 10, and the finest degree of feed 1/500 in. The 
regular section-knives as well as the ordinary razors can be used with 
the instrument.” 
C4) Staining- and Injecting-. 
Brown-staining Bacillus.* — Herr D. Scheibenzuber describes a 
bacillus which he has isolated from rotten plover’s eggs, and of which 
the chief characteristic is that it stains the gelatin in the immediate 
vicinity of the colonies of a brownish colour. The colonies when grown 
on plates are stated to consist of a central area, which is surrounded by 
a radiately striated zone. The gelatin surrounding the colonies is 
not liquefied ; when cultivated in test-tubes (puncture cultivation), the 
inoculation track becomes characteristically serrated, and produces a 
brown pigment. 
When examined with 1/20 oil-immersion the micro-organism is 
found to be a short bacillus pointed at both ends. 
New Method for Staining and Mounting Tubercle Bacilli. | — 
Dr. H. Kiihne recommends the following method for staining tubercle 
bacilli : — 
After the cover-glasses have been prepared, that is, coated with 
sputum and dried in the flame, they are stained in carbolic fuchsin for 
five minutes. They are then thoroughly decolorized in 30 per cent, 
nitric or sulphuric acid, and subsequently washed in water and dried. 
After this they are examined in a drop of anilin oil stained slightly 
yellow with picric acid. This mixture is best made by adding 2 to 3 
drops of concentrated solution of picric acid in anilin oil to a capsule 
full of anilin oil. 
Preparations obtained in this way will remain fit for examination 
for at least a week. If permanent preparations are desired, the cover- 
glass, after it has been decolorized by the mineral acid, is placed for 
some minutes in an aqueous solution of picric acid, then dried and 
mounted in the usual manner. 
Staining Flagella of Spirilla and Bacilli.j: — Dr. Trenkmann finds 
that the flagella of bacteria may be stained with very satisfactory results 
in the following manner : — 
The cover-glass having been prepared from a cultivation in the 
usual manner, is immersed for 6 to 12 hours in a solution of 2 per cent. 
* Mittheil. aus d. Embryol. Institute d. K. K. Univ. Wien, 1890, pp. 1-9 (4 figs.). 
f Centralbl. f. Bakteriol. u. Parasitenk., viii. (1890) pp. 293-7. 
X T. c., pp. 385-9. 
