THE INFLUENCE OF BAROMETRIC PRESSURE ON 

 CARBON-DIOXIDE EXCRETION IN MAN^ 



G. O. HIGLEY 

 (Ohio Wesleyan University, Delaware, Ohio) 



(WITH PLATE 5) 



Introduction. This work was suggested by that of Lombard^ 

 on " Some of the influences which affect the power of muscular 

 contraction." In that research, which was made with the ergo- 

 graph, Lombard found that, in general, there was a fall of muscular 

 power during the day, this result being noted on eighteen out of a 

 series of twenty-three days. However, on certain days, the fall in 

 power due to fatigue was slight and on five days the power was 

 greater at the last experiment than at the first. These exceptions 

 led to the suspicion that barometric changes had an influence on 

 muscular endurance. When, later, a comparison was made between 

 Lombard's endurance curve and the curve of barometric height, it 

 was found that, while no constant relationship existed between the 

 two variables, they varied in the same sense on twenty out of twenty- 

 three days ; i. e., in general " when the barometer rose during the 

 day, or feil less than on the preceding day, the muscular endurance 

 either rose, or feil less than on the preceding day." 



It has been shown, furthermore, that while a diminution of 

 barometric pressure increases both the respiration rate and the 

 volume of air respired, after allowance is made for the increase of 

 volume due to the lower pressure the volume respired is less 

 (Speck). 



Now, the effect of increasing barometric pressure upon the power 

 of the muscular System might possibly be due to some influence 



^ This paper was accepted for publication by the officers of Section VIII, 

 d, Eighth International Congress of Applied Chemistry, and was read before the 

 Section at a stated meeting on September 11, 1912; Biochemical Bulletin, 

 1912, ii, p. 153. 



^ Lombard : Journal of Physiology, 1892, xiii, p. i. 



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