346 MAN AN ADAPTIVE MECHANISM 



other words, morphin interferes with the normal 

 mechanism by which acidity is neutralized, possibly 

 because its depressing action on the respiratory center 

 is sufficient to overcome the stimulating action of 

 acidity on that center, for, as we have stated, the 

 neutralization of acidity is in large measure accom- 

 plished by the increased respiration induced by the 

 acidity itself ; possibly also because morphin prevents the 

 output of adrenin, and adrenin measurably governs the 

 great acid-reducing organ the liver. 



Acidosis in Relation to Normal and Pathologic 

 Phenomena 



If, as is now believed by physiologists, the respira- 

 tory center is governed by the H-ion concentration of 

 the blood, rather than by the want of oxygen merely, 

 then the elimination of the by-products of metabolism 

 is of paramount importance in the maintenance of the 

 health of the organism ; and its clinical significance, as 

 pointed out by many observers, notably Fisher, Hen- 

 derson and Michaelis, is obvious at once. 



In my laboratory many observations have been made 

 to determine the effect of the excision or functional de- 

 pression of certain organs on the normal reaction of 

 the blood and of the urine. When the liver is excised, 

 the alkalinity of the blood is rapidly diminished and 

 death follows. When the adrenals are excised, the 

 blood maintains its normal reaction for a longer time 

 perhaps twice as long but then its acidity increases 

 rapidly and death follows. (Figs. 83, 84.) When con- 

 nection between the brain and the remainder of the 

 body is broken at the medulla, the blood remains normal 



