and dry points. Sometimes the total contents of 10 or 12 tubes ^vere 
injected subcutaneously into guinea pigs or mice. In another series 
the virus from ivory points or capillary tubes was planted in fresh 
broth and grown anaerobicallv. and the resulting growth studied for 
end-spore-forming rods and also inoculated into animals. In no case 
was an organism or were symptoms resembling tetanus found. 
While these results were most gratif ving. thev must not be taken as 
conclusive that tetanus may not sometimes contaminate vaccine virus, 
although from our studies this must be exceedingly rare. Tetanus 
organism can not grow or produce its toxin either in the glycerinated 
virus or on the dry points. It would take gross carelessness to con- 
taminate the vaccine with a sufficient number of tetanus spores to 
carry the disease to those vaccinated. 
It is not a matter of surprise that some outbreaks of tetanus have 
occurred when thousands of open wounds are presented for the recep- 
tion of this infection so widely distributed in nature. Local outbreaks 
or small epidemics of tetanus have been known before the days of 
antiseptics, due to causes so well understood nowadays, and it seems 
more likely that carelessness in the dressing or handling of the wound, 
the pernicious use of shields, or faulty technique in performing the 
operation has introduced the tetanus spores, than that they were con- 
tained in the vaccine virus. 
Wost of the following work on tetanus was done under mv direction 
by Dr. Edward Francis, and it is a pleasure to acknowledge the care 
and faithfulness with which he carried out all the exacting details. 
VIABILITY OF TETAXUS IX VACCIXE VIBES. 
Can tetanus live and grow in vaccine virus ? 
In order to answer this question we contaminated vaccinal serum 
and the glycerinated pulp with tetanus spores. The serimi was dried 
upon ivory points and the glycerinated pulp was conserved in capillary 
tubes in a manner similar to the methods now used by the manufactur- 
ers. From time to time these points and tubes were examined. 
For the purposes of these experiments it was thought best to use a 
pure culture of tetanus for one series of experiments and for another 
series to use a mixed culture composed of tetanus, a coccus, and a 
motile, spore-bearing, saprophytic rod. as representing more nearly 
the natural conditions under which tetanus would be found to gain 
entrance into vaccine. 
The pure culture of tetanus used in these experiments was taken 
from our laboratory stock culture. It was planted into ordinary 
bouillon on March 2 and grown anaerobically in a 2sovy jar at 37^ for 
seven days, when it contained abundant spores. 
VIEELEXCE OF THE TETAXES CELTERE ESED. 
In order to determine the virulence of the pure culture of tetanus 
used it was tested in vliite mice, with the following results. Each 
