68 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
typhoid fever, on ten cases of other febrile diseases, and on normal 
blood. Positive results were obtained with the typhoid fever cases 
only. The reaction is usually obtained from the fourth day to long 
after the fifth week. After the ninth day the reaction is usually in- 
stantaneous. Though the action can be obtained with dry serum, its 
immobilising and agglutinative properties are sooner lost than those 
of fluid serum. 
According to Dr. H. E. Durham, * the reaction is not always 
obtainable, for in a series of ten cases no reaction occurred in four, 
and he concludes that an absolute diagnosis cannot always be made 
by this method. The best procedure for obtaining serum is to prick 
the lobule of the ear and allow 0 • 2-0 * 3 ccm. of blood to trickle into a 
test-tube held horizontally. After the blood has clotted, the serum can 
be removed, or the blood may be slowly centrifuged. 
Dr. A. S. Griinbaum,'j' who made experiments on the agglutinative 
action, states that it is only in cases of enteric fever that the serum 
shows a distinct agglutinative action within 30 minutes, when diluted 
sixteen (or more) times. The method recommended is to take blood 
from the ear, and centrifugalise it in a U-shaped capillary tube. The 
serum is afterwards blown on to a slide and then mixed with bouillon. 
An emulsion of typhoid bacilli in bouillon is then made, and the mixture 
examined to make certain there are no clumps therein. A small drop of 
the diluted serum and a similar drop of the emulsion are mixed on a cover- 
glass and examined as a “ hanging drop.” If the bacilli aggregate in 
'dumps with impaired or lost mobility within 30 minutes, the reaction 
indicates enteric fever. The reason for diluting the serum is that if 
undiluted the serum of enteric fever patients may exhibit a stronger re- 
action with the cholera vibrio or Bac. coli com. than with B. typhosus. 
The time limit is necessary, because almost every human serum, even 
when diluted, will eventually produce an agglutinative action. 
Diphtheria or Diphtheroid Bacilli in Empyema Pus.f — Dr. J. 
Trumpp records a case of empyema from which was isolated, among 
other microbes, a bacillus having the morphological characters of Ba- 
cillus diphtherise Loeffler. Even grape-sugar bouillon became acid in 
24 hours, and showed a flocculent deposit. Experiments on animals 
showed, however, that the cultures were devoid of virulence. This 
absence of virulence raised the question whether the bacillus was that 
of true diphtheria, pseudodiphtheria, or a diphtheroid organism. The 
question was answered by injecting a guinea-pig with 0*35 ccm. of 
diphtheria toxin as well as the cultivation. In this way virulence was 
regained, and by the third remove the animal died in 12 hours. This 
method of restoring the virulence is apparently new, and is certainly 
simple. 
* Tom. cit., p. 1746. f Tom. cit., pp. 806 and 1747. 
X Centralbl. f. Bakteriol. u. Parasitenk., l te Abt., xx. (1896) pp. 721-5. 
