142 



The Philippine Journal of Science 

 Table III. 



1913 



No. of 

 animal. 



10 



Anti- 

 tetanic 

 serum 

 units. 



Date. 



Tetanus 



toxin test 



dose. 



Date. 



Days 

 after 

 serum. 



Result. 



250 



May 18,1911 



0.05 



June 27. 1911 



40 



Died. 



11 



250 



May 22,1911 



0.05 



do - 



36 



Died. 



12 



250 



May 26,1911 



0.05 



do 



32 



Lived. 



13 



250 



May 30,1911 



0.05 



do 



28 



Lived. 



14 



250 



June 3,1911 



0.05 



do 



24 



Lived. 



15 



250 



June 7,1911 



0.05 



do 



20 



Lived. 



16 



250 



June 11,1911 



0-05 



do 



16 



Lived. 



17 



250 



June 15. 1911 



0.05 



do 



12 



Lived. 



18...... 



none 





05 



do 





Died 















The results shown in Table III were as follows: Guinea pigs 

 10 and 11 and the control 18 died. All others lived. The results 

 obtained in experiment 3 were identical with those obtained in 

 experiment 2. 



CONCLUSIONS 



The following conclusions seem justified: 



1. The subcutaneous injection of 1,500 units of antitetanic 

 serum from horse into horse confers passive immunity of be- 

 tween six and eight weeks' duration. 



2. Guinea pigs subjected to repeated inoculations with anti- 

 tetanic serum from horse do not acquire the power to eliminate 

 it more rapidly; they acquire a tolerance as is shown by the 

 longer period of immunity. 



3. After repeated injections of normal horse serum into guinea 

 pigs, passive immunity, following the injection of antitetanic 

 serum from horse, is of longer duration than it is in untreated 

 guinea pigs. 



