28 
Scientific Proceedings (40). 
The autopsy showed undissolved bodies of tubercle bacilli 
spread over the omentum. 
Pig No. 2. Some restlessness but no other sign that it was 
affected by the injection. Two days later this pig was seized with 
a convulsion and died. 
The autopsy showed undissolved bodies of tubercle bacilli not 
spread over the omentum but collected together in small groups- 
The edge of the spleen was covered with small abscesses which did 
not show tubercle bacilli. 
The serum of rabbits treated according to experiment two (2) 
acquired a clumping property for the tubercle bacilli. This was 
shown by each of the two rabbits that are now duplicating the 
successful experiment No. 2. 
An emulsion of bovine tuberculosis was mixed with clear serum 
drawn from these animals six days after the last injection. 
A mixture of this serum from each rabbit and a uniform sus- 
pension of tubercle bacilli after standing overnight at room tem- 
perature was found to cause well denned clumping. The control 
in normal sodium chloride solution was not clumped. 
A knowledge of substances which counteract the toxic effects 
of the infecting organism is of great value in attempts at immu- 
nization. 
The fact that " tuberculin" the toxic extract of the tubercle 
bacillus is an arterial blood depressor immediately suggests that 
the extract of the suprarenal gland might antagonize it. We 
have carried out experiments of this nature and find that according 
to the amount of tuberculin and suprarenal extract in the mixture 
one can produce a depression or rise at will. 
The depressor substance in tuberculin then can be measured 
by suprarenal extract of known strength. 
If the depressor substance in tuberculin is a necessary constit- 
uent for tuberculin as a diagnostic and therapeutic agent, then we 
have an easy and simple method of measuring its strength. 
We have injected tuberculin into dogs from which we have 
removed one and both suprarenals. The results bear out the 
theory, but have brought to light so much that is new and inter- 
esting that we will reserve the discussion for a future paper. 
