66 (130) Society for Experimental Biology and Medicine. 



a considerable fall of the blood-pressure, while Edmunds states, in a 

 recent report from Halliburton's laboratory, that the effect is an 

 insignificant one. 



Nearly all of the investigators of this question within the last 

 fifty years have employed bile salts in their experiments. The re- 

 sults of the authors' experiments were derived from intravenous 

 injections of filtered ox bile into rabbits. Of the several reasons 

 for employing bile and not its salts, one should be mentioned : It 

 is the belief of the authors that for biological phenomena we have 

 as yet no right to assume that the sum of the known parts is equal 

 to the whole. 



In these experiments all degrees of effects have been observed, 

 from an insignificant one to a considerable and even a fatal fall of 

 blood-pressure. But these different degrees could be produced 

 at will. Besides the quantity and the concentration of the bile, it 

 was found that the rate at which it is introduced into the circula- 

 tion is the most effective factor in the result. A quantity of bile 

 of a given concentration, which, when injected slowly, would cause 

 only an insignificant depression, brought about a tremendous fall 

 of the blood-pressure when injected rapidly. By injecting normal 

 salt solution speedily the fact has been established that neither the 

 mechanical influence of the rate of injection nor the temperature 

 of the injected fluid can have anything to do with the pronounced 

 effect which is invariably produced by the rapid injection of bile. 

 Although the speed of introduction was known to be a factor in 

 the results produced by injections of other substances, it was never 

 taken into consideration in the studies of the effects of bile. Thus, 

 there are also conflicting statements regarding the immediately fatal 

 effect of intravenous injections of bile. These contradictions find 

 their satisfactory explanation in variations in the rate of injection 

 employed in different experiments. Thus, a quantity of bile which, 

 when injected slowly would produce hardly any symptom, causes 

 death within two minutes if injected rapidly. 



As to the cause of the fall in pressure, or of the fatal outcome, 

 it is generally assumed that it is due to the effect of the bile upon 

 the heart, although opinions differ as to whether it is the heart 

 muscle or the heart ganglia which present the points of attack. 

 As to the manner of the injury, Traubc, Leyden and other investi- 



