A HISTORY OF METABOLISM 31 



Place, Berthollet, Gay-Lussac, Thenard, Cuvier, Ampere, Laennec and 

 Magendie. 



Thorpe writes of them (1908) : 



"That constellation has set 



'The world in vain 

 Will hope to look upon their like again.' ' 



The atmosphere for the development of French science reached at 

 this- time a maximum of power to stimulate. One of the few mistakes 

 of Lavoisier was his conception that oxidation took place in the lungs. 

 Lagrange, the illustrious mathematician, a friend and associate of La- 

 voisier, reflecting that if the heat production took place in the lungs their 

 temperature must be higher than elsewhere in the body, concluded that 

 heat was generated wherever the blood circulated, that oxygen dissolved in 

 the blood, combined with hydrogen and carbon there, and that carbonic 

 acid was eliminated. This interpretation of Lagrange was published in 

 1791 before Lavoisier's death by Lavoisier's pupil Hassenfranz (Z), who 

 agrees that the caloric necessary to maintain animal heat is liberated in the 

 blood by the combination of carbon and hydrogen with oxygen, with which 

 the blood is mixed. 



Humphrey Davy (1778-1829) was the first to obtain oxygen from 

 arterial blood by warming it to 93 C. and carbonic acid from the venous 

 blood by warming it to 45 C. He was apparently not well acquainted 

 with Lavoisier's work, and his own work, published in 1799, remained long 

 forgotten. To him oxygen occurred as "phosoxygen," a combination of 

 heat and light. In his experiment XVII he shows that "phosoxygen" can 

 be absorbed by venous blood in the dark without the liberation of light, 

 but with the result that the color of the blood changes from dark red to 

 bright vermilion. 



Experiment XVIII. 



A phial containing about 12 inches, having a pneumatic apparatus affixed to 

 it, was filled with arterial blood from the carotid artery of a calf. The phial was 

 placed in a sand bath at a temperature of 96 and the heat gradually and slowly 

 raised. In about ten minutes the temperature of the bath was 108 and the blood 

 began to coagulate. At this moment some globules of gas were perceived passing 

 through the tube. Gas continued to pass in very small quantities for about half 

 an hour when the temperature of the sand was about 200; the blood had coagu- 

 lated perfectly and was now almost black. About 1.8 cu. in. of gas were collected 

 in the mercurial apparatus; of this 1.1 cu. in. were carbonic acid and the re- 

 maining 0.7 phosoxygen. 



From this experiment it is evident that the arterial blood contains phosoxy- 

 gen, and we have proved before by synthesis that it is capable of combining with 

 it directly. We are possessed of a number of experiments which prove that 

 phosoxygen is consumed in respiration. It has been likewise proved that gases 

 can penetrate through moist membranes like those of which the vessels of the 

 lungs are composed. We may therefore conclude that phosoxygen combines 



