76 THE PHYSIOLOGY OF THE ADRENALS. 



of the scarcity of the gas in the surrounding atmosphere. In- 

 deed, the air in the pulmonary vesicles contains 8 per cent, 

 of carbonic acid, hardly a favorable condition for the escape of 

 carbonic acid from the blood, especially since a portion of this 

 gas is not dissolved, but combined with the serum salts. It is 

 therefore probable that the pulmonary tissues are the seat of 

 an action having for its object to rapidly dislodge the carbonic 

 acid. This action is probably of a chemical nature. 153 . . . 

 Whenever oxygen is mixed with venous blood, even in vitro 

 during experiments, the carbonic acid is immediately given off. 

 One is led to admit, therefore, that the combination of oxygen 

 with the blood-corpuscles (oxyhaemoglobulin) plays a role 

 analogous to that of an acid, and involving the elimination of 

 carbonic acid from venous blood." He refers to Eobin and 

 Verdeil's view in respect to the existence of a hypothetic 

 "pneumonic acid" and to the experiments of Gamier, 154 who 

 observed that ultramarine blue sprayed into the lungs of living 

 guinea-pigs lost its color: a phenomenon which could only 

 occur through the presence of a strong acid, neither taurin 

 nor carbonic acid being capable of producing it. "Chemical 

 analysis of the lung has not disclosed a specific acid, however." 

 . . . "It is, perhaps, wrong," adds Professor Duval, "for 

 physiologists to continue to only see in these phenomena mere 

 results of endosmosis of liquids and of diffusion of gases 

 through an inert membrane." 



To study this question satisfactorily, however, and place 

 the deductions reached upon a strong footing, it is necessary 

 to clearly define the relations between the various bodies con- 

 cerned in the process. All the phases of the problem, physio- 

 logical and pathologi2al, must therefore be analyzed. The fol- 

 lowing facts, however, seem to afford a firm foundation for the 

 inquiry: 



1. The adrenals secrete a colloid substance which penetrates 

 the lungs with the venous blood and cannot be traced beyond these 

 organs. 



2. The secretion of the adrenals possesses a marked affinity 

 for oxygen. 



163 The italics are our own. 



"" Gamier: Comptes-Rendus de 1' Academic des Sciences, July 26, 1886. 



