206 Dr. A. E. Wright and Staff-Surgeon S. T. Keid. [Oct. 21, 



infection a lowered " bacteriotropic pressure " which accounts for the 

 cultivation of the pathogenetic microbe in the interior of an organism which 

 has at disposal in the circulating blood a considerable reserve of anti- 

 bacterial substances. We propose here in conclusion to furnish further 

 illustration of the general law as enunciated above, culling our examples 

 not alone from the observations we have made in connection with tubercular 

 infection, but also from observations made in connection with other bacterial 

 infections. 



Observation 1. — Case of abscess in the neighbourhood of the appendix. 

 Blood from the patient's finger and pus obtained from the abscess at the 

 operation were examined, with a view to determining the nature of the 

 infection. 





Phagocytic counts. 



With a suspension of 

 tubercle bacilli. 



With a suspension of 

 staphylococci. 





2 3 



4-5 



Fluid obtained from the 



o-i 



i-9 



pus by centrif ugalisation 







The fact that the tuberculo-opsonic power of the patient's blood was 

 here 23 times as great as that of the fluid obtained from the pus was taken 

 as evidence that tuberculo-opsonic substances had been used up in the pus 

 and that the patient was suffering from a tubercular infection. It was 

 inferred on similar grounds that he was also infected by staphylococcus. 



Observation 2. — Case of osteo-myelitis of the femur. Blood from the patient's 

 finger and pus obtained from the abscess at the operation were examined, 

 with a view to determining the nature of the infection. 





Tuberculo-opsonic 



Staphylo-opsonic 





index. 



index. 





1'0 



2-5 



Muid obtained from the 



1 -1 



0-9 



pus by centrif ugalisation 







The fact that the opsonic index of the patient's circulating blood was here 

 normal to tubercle, while it was two and a-half times greater than normal 



