Factor in the Mechanism of Bacterial Infection. 



525 



produce tetanus in every case when injected together with a rupturing dose 

 of a calcium salt. 



The details of the experiment are given in the following Table. It is 

 perhaps necessary to point out that this experiment is quite different from 

 those mentioned in an earlier part of this paper, in which tetanus spores 

 were injected first and then calcium salts. 



Tetanus. Effect of separating Time and Site of Injections of Bacteria and of 



Calcium Salt. 



Batch. 



No. of 

 mouse. 



Dose of Ca 

 nitrate. 



Interval of 

 time.- 



Site. 



Result after 

 1 2 3 4 days. 



- i { n 



mgrm. 

 2-5 



2-5 



hours. 



2i 



2i 



Same 

 Different 



o o o o 

 o o + o 

 o o 1 o 

 o o 1 o 



c 



D 



{ l\ 

 { 1} 



5 

 5 



24 

 2i 



Same 



Different 

 • 



1 1 oo 

 I 1 oo 



o o o o 



E 

 F 



{lU 



10 

 10 



24 

 24 



Same 

 Different 



Moo 

 1 1 oo 

 + + o o 

 o o o o 



G 

 H 



{in 



{!?} 



5 

 5 



24 

 24 



Same 

 Different 



r + 

 [ 



r 



t 



J 



K 



{15} 



10 

 10 



24 

 24 



Same 

 Different 



1 1 oo 

 1 + o o 

 + o o o 

 o o o o 



Control 



r 21 ^ 



1 22 1 

 ! 23 1 



1 24 r 



I 26 J 



Spores alone 







o o o o o o 

 o c o o o o 

 o o o o o o 

 o o o o o o 



means alive and well with absence of symptoms of tetanus. + means died with symptoms 

 of tetanus. 



All these experiments point to the conclusion that the injection of calcium 

 salts produces at the site of injection a local change in the tissues of the 

 animal since the specific disease is most easily elicited when the calcium 



