432 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
S. Technique.* * * § 
Cl) Collecting Objects, including Culture Processes. 
Mode of keeping Fresh-water Animals alive. f— Dr. J. Dewitz 
recommends the spreading of a piece of canvas or small dampened towel 
over the bottom and side of a plate on which the fresh-water animals 
are placed. They must then be covered with another wet towel and put 
in a cold room. The towels must be washed and wrung out every fourth 
day, and any dead specimens removed. 
Antibacterial Value of Aristol.J — In order to estimate the anti- 
bacterial value of aristol, Dr. Heller inoculated agar plates with Staphylo- 
coccus aureus, putrefactive bacteria, and anthrax. Some of the plates 
were covered with iodoform, and others with aristol. The capsules 
were then incubated at 37° ■ 5 for 2-3 days in the absence of light, 
sufficient moisture being supplied by water placed in other capsules. 
No further development was found on the plates strewn with iodoform, 
but on those covered with aristol there was a luxuriant growth, except 
where the layer happened to be very thick, a result probably due to the 
mechanical exclusion of air. Hence it would seem that the antibacterial 
value of aristol is small, and, at any rate, not to be compared to that of 
iodoform. 
Effect of Centrifuging on Bacterial Suspension, with special 
reference to the Dissemination of Bacteria in Milk.§ — After having 
ascertained by experimenting with anthrax that an hour’s centrifuging at 
the rate of 2000-4000 turns a minute was not detrimental to the vitality or 
the virulence of these organisms, Herr Scheurlen turned his attention 
to the behaviour of bacterial pure cultivations in suspension. 
The results of centrifuging were found to depend on the mobility or 
immobility of the bacteria, the latter tending to be thrown out and to 
form a sediment, while some of the former, e. g. Cholera vibrio and 
Proteus mirabilis, remained suspended. 
The author theu examined the behaviour of the bacteria of milk when 
similarly treated. After centrifuging, the milk-scum, when tested by 
means of plate cultivations, showed, as was to be expected, a large 
number of colonies, while the number in the cream was also very great, 
and might even exceed that of the scum. 
The author infers from the experiments that milk cannot be freed 
from its bacteria by centrifuging, for out of 2050 millions of germs in 
the whole volume of milk, only 18 millions were removed in the scum. 
About three-fourths of the number are transferred by the centrifuging 
to the cream, the remainder being in the buttermilk. 
Most pathogenic microbes, such as anthrax, typhoid, and cholera, 
cling to the cream like the milk-bacteria, but tubercle bacilli were for 
* This subdivision contains (1) Collecting Objects, including Culture Pro- 
cesses; (2) Preparing Objects ; (3) Cutting, including Imbedding and Microtomes; 
(4) Staining and Injecting: (5) Mounting, including slides, preservative fluids, &c. ; 
(6) Miscellaneous. f Zool. Anzeig., xv. (1892) pp. 105-6. 
J Arch. f. Derm. u. Syphilis, 1891, p. 840. See Ceutralbl. f. Bakteriol. u. Para- 
sitenk., xi. (1892) p. 351. 
§ Arbeit, a. d. Kaiser. Gesundhcits-amte, vii. (1891) See Centralbl. f. Bakteriol. 
u. Parasitenk., xi. (1892) pp. 53-4. 
