712 FRANCIS H. McCRUDDEN 



carried out experiments that would have anticipated a century of errors. 

 But scientific work was soon interrupted by the French Revolution, 3 and 

 Lavoisier himself was executed early in 1794. 



In 1849, Regnault and Reiset, and in 1858, Miiller, as a result of 

 experiments similar to those of Lavoisier, again pointed out that the 

 activity of the metabolism remains unaffected by the oxygen tension. In 

 1838, Miiller (a) stated clearly that oxidation does not take place in the 

 blood, but in the tissues ; he believed, however, that the respiration is not 

 the result, but the cause of oxidation. The facts regarding internal res- 

 piration were stated correctly by 'Vierordt in 1844. According to Vierordt, 

 oxidation takes place in the tissues, the blood merely transports the oxy- 

 gen to the tissues and the carbon dioxid away from the tissues. Experi- 

 mental confirmation of these hypotheses was furnished in 1857 by L. 

 Meyer. Meyer demonstrated that the blood transports both oxygen and 

 carbon dioxid. 4 A further confirmation of this theory was furnished in 

 1863 by Panum, who showed that the amount of oxygen absorbed, and the 

 amount of carbon dioxid given off is not affected by the great loss of trans- 

 porting power for oxygen which results from severe hemorrhage. But 

 these experiments seem to have made but little impression at the time. 

 In the subsequent polemics, these writers are given little credit; Pfliiger, 

 indeed, in 1868 rejected Meyer's conclusion (Pfliiger and Zuntz). 



Almost inextricably involved with the incorrect theories regarding 

 the cause of oxidation, was an incorrect theory concerning the place of 

 oxidation. Oxidation was believed to take place, not in the tissues, but 

 in the blood stream. It was the gradual accumulation of data, not in 

 harmony with this latter belief, and indicating that oxidation takes place 

 in the tissues, that led to a readjustment of the views regarding the cause 

 of oxidation. 



Voit in 1866, was probably the first to incline physiologists to the 

 belief that respiration is not the cause of metabolism, but the result of 

 the needs of the metabolism (Lossen(a), Pettenkofer and Voit). He 

 pointed out that the carbon dioxid eliminated is independent of the 

 ventilation of the lungs. 5 In 1868 he showed that neither by section of 

 the vagus, formation of a pneumothorax nor by hemorrhage, whereby res- 

 piration is diminished, can the amount of oxygen taken up, or the amount 

 of carbon dioxid given off, be influenced (Voit(&)). In 1869 he showed 

 that in leukemia a disease which was believed to lead to a diminished 

 internal respiration 6 neither the oxygen intake nor the carbon dioxid 



The memoirs of the French Academy for 1790 were not published until 1797. 

 A new set starting with volume I began in that year. The intervening years are not 

 represented. The Academy was suppressed in 1793. 



* Twenty years before, by means of a mercury pump, G. Meyer had extracted carbon 

 dioxid and oxygen from both arterial and venous blood. 



11 Confirmed also by later experiments (Voit(e), Lossen(6) ). 



8 Salkowski (a) studied this problem, too, and could find no products of incom- 

 plete oxidation in the urine of patients with leukemia (Salkowski (a) ). 





