ANALYTICAL EVIDENCE. 321 



Sir David Barry, ibid. 234, and those of Poiseuille, ibid. 

 Miiller, although not admitting to their full extent the in- 

 ferences of Barry, admits that by the sucking of the heart, 

 and by the action of the valves, a part of the resistance 

 which opposes the course of the venous blood is overcome. 



EXCRETION OF CARBON. 



Berzelius considers the quantity of carbonic acid in all 

 the calculations, as given p. 271, to be too great, for the 

 solid food taken into the body contains fths of its weight of 

 water, and of the other |th, seldom more than | is carbon ; 

 consequently 6| Ibs. of solid food would be necessary to 

 supply the quantity of carbon which, according to these 

 estimates, is excreted from the body by the lungs in 24 

 hours, independent of what is got rid of in other ways. 

 Mulder, 1-308. 



