PROTECTIVE INOCULATIONS. 335 
‘‘ Applicability at any time during the period of incubation up to the 
moment of the appearance of symptoms of rabies ; absolute absence of viru- 
lence and of any injurious action ; very rapid treatment by the injection of 
one or several small doses of material ; complete solubility and consequently 
prompt absorption of the material injected and its easy preservation in a dry 
condition.” 
INFLUENZA. 
The bacillus discovered by Pfeiffer, in 1892, is now well estab- 
lished as the specific cause of this disease. Bruschettini has recently 
(1893) reported the details of his experiments upon rabbits, for which 
animals this bacillus is pathogenic. As a result of these experiments 
he has reached the following conclusions: 
‘‘1. Rabbits may be vaccinated against the pathogenic action of cultures 
of the influenza bacillus without great difficulty. 
‘2, The best material for producing a high grade of immunity is blood 
cultures which have been filtered through the Berkenfeld filter. 
‘3. The blood serum of immunized animals has strong antitoxic proper- 
ties, but has no germicidal power. 
‘4, The serum of vaccinated animals has the power of conferring im- 
munity upon other animals, in comparatively small amounts—in the pro- 
portion of 1:42,000 of body weight, and perhaps still less. 
‘*5. This serum has also a decided curative action, and rescues rabbits 
from death even as late as forty-eight hours after infection by injection of a 
culture of the bacillus into the trachea.” 
These results lead the author to hope that serum-therapy may 
afford a method of curing this disease in man. For this purpose the 
blood of an immune rabbit would appear to be the most promising 
source from which to procure an antitoxic serum. 
INFLUENZA IN HORSES. 
Scuitirz (1887) has described a minute oval bacillus, usually asso- 
ciated in pairs, which appears to be the specific infectious agent in 
the disease known in Germany as Brustseuche. This bacillus is path- 
ogenic for mice, rabbits, pigeons, and guinea-pigs, but not for swine 
or chickens. By injection of cultures into the parenchyma of the 
lungs Schiitz reproduced the disease—confirmed in 1888 by Hell. 
Horses which have suffered an attack of infectious influenza are 
subsequently immune, and the experiments of Hell have shown that 
an immunity also follows the disease which results from inoculations 
with pure cultures of the Schiitz bacillus. 
The extended experiments made by the War Department of the 
German Government show that the disease is not produced by intra- 
venous injections or by the ingestion of the bacillus with the food. 
Infection occurs, however, when cultures are injected into the re- 
