848 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
Influenza Bacillus.* — Drs. Pfeiffer and Beck, who have been making 
further investigations on influenza germs, have not been able to detect 
influenza bacilli in the blood, and declare that the bacilli bred by Canon 
from blood of influenza patients are not identical with the bacilli described 
by them. The latter are found as a rule and exclusively in broncho- 
pneumonia foci and on the bronchial secretion of influenza patients. 
To find the bacilli in the sputum the greenish-yellow viscid particles 
must be examined. Cover-glass preparations and celloidin sections of 
broncho-pneumonia portions of lung were stained in Ziehl’s solution 
(10-20 times diluted) for 10-30 minutes ; they were then carefully 
decolorized in absolute alcohol and cleared up in xylol. The bacilli, 
somewhat shorter and slenderer than those of mouse septicaemia, were 
found both within the cells of the cover-glass and in section preparations, 
and also free. 
The authors failed to cultivate the influenza bacilli on glycerin- 
agar, and the only successful medium was made by rubbing a drop of 
healthy human blood on agar. The inoculation material was obtained 
from flakes of bronchial secretion carefully removed from the sputum. 
After a microscopical examination had demonstrated the absence of 
foreign micro-organisms, the flakes were rubbed up with 1 cem. of 
sterile water. The cultivations reached their maximum in the incubator 
in about 48 hours, after which they soon died. The colonies were very 
minute and resembled little drops of water. 
Apes when inoculated with this bacillus underwent a febrile 
condition lasting some days, but all other animals were immune. 
The bacilli quickly die when dried, when heated up to 60°, and from 
the action of chloroform. They are found in influenza sputum for 
some days after the febrile stage of the disease has passed off, but then 
lie chiefly within the cells, stain badly and cannot be cultivated. 
Bacteriology and Butter-making.| — Herr H. Weigmann has some 
notes on this subject. Butter which comes into the open market is of 
two sorts, the sweet and the sour ; the latter owes its characteristic 
flavour and aroma to fermentation products, the result of the lactic 
fermentation taking place in the cream. 
Now the number of bacteria in air, water, &c., capable of setting up 
the lactic fermentation is not small, and many of these impart disagree- 
able flavours and odours to butter ; indeed the proper consistence may 
be impaired or lost. 
As cream is not suitable for pasteurization, the obvious method, 
instituted by the author and now carried out in many dairies with great 
success, was to acidify the cream with a pure cultivation of a lactic acid 
bacterium of known properties and approved action. In practice the 
new method consists in keeping some centrifuged or skim milk (about 
2-3 per cent, of the bulk of cream to be made into butter) for 3-4 hours 
at a low temperature. It is next heated to 25°, and then inoculated with 
the bacteria cultivation. The inoculated milk is then placed in a warm 
room until the acid is ready for use. 
* Deutsche Med. Woclienschr., 1892, No. 21. See Centralbl. f. Bakteriol. u. Parasi- 
tenk., xii. (1892) pp. 33-4. 
f Milch-Zeitung, 1890, p. 945. Landw. Wochenbl. f. Schleswig-Holstein, 1892, 
No. 16. See Centralbl. f. Bakteriol. u. Parasitenk., xi. (1892) pp. 762-4. 
