FUNCTION OF THE BLOOD-CELLS. 275 



reference to morphological progressive and regressive development, 

 vitality can no more be denied to the blood-corpuscles than to any 

 other animal or vegetable cell. 



An opinion long prevailed that the blood-corpuscles took up 

 oxygen in the lungs and gave it off in the capillaries, the view being 

 based upon the bright red colour of the blood in the lungs, and its 

 darkness in the capillaries. These cells were in fact regarded as 

 carriers of oxygen. Henle refutes this view by observing that we 

 might, with equal justice, also term them water-carriers, since they 

 show themselves no less capable of absorbing the smallest addi- 

 tional quantity of water than of taking up oxygen and carbonic 

 acid ; for they absorb water, and again give off a portion of it, in a 

 state of vapour, in the lungs ; the gases through whose assumed 

 chemical action this function of the cells was supposed to be 

 derived, could only exert a mechanical influence on the form, and 

 therefore on the colour of the blood-cells. This opinion derived 

 great probability from Mulder's careful investigation of hsematin, 

 which was found to be perfectly indifferent to gases, and likewise 

 from the above named inquiries of Nasse, Henle, Scherer and Bruch, 

 who have shown the influence exerted on the colour of the blood 

 by the alterations in the form of the cells. There are, moreover, 

 two other facts which appear to render this supposed function of 

 the blood-cells exceedingly doubtful, if not wholly untenable ; in 

 the first place, Marchand could not obtain the slightest trace of 

 carbonic acid in blood through which oxygen had been passed after 

 the removal of all the gases; the conversion of oxygen into 

 carbonic acid cannot therefore take place within the cells them- 

 selves. Another observation, made by Hannover, speaks, however, 

 still more strongly against the usually adopted view; for this 

 observer found that chlorotic patients, whose blood is often exceed- 

 ingly deficient in coloured blood-cells, exhaled in like periods of 

 time as much carbonic acid as healthy women. Hence we might be 

 disposed to believe with Henle, that there is no intimate relation 

 between the corpuscles and the gases of the blood, if there were not 

 two important grounds, supported on facts admitting of only one 

 interpretation, which are in favour of the view according to which 

 the blood-cells possess the capacity of absorbing oxygen. The 

 first of these grounds rests upon the observation already referred 

 to, that neither the intercellular fluid nor the serum alone has 

 the power of absorbing more than a small quantity of oxygen, 

 while the cell-containing blood exhibits a very strongly marked 

 capacity for absorption : a fact that speaks so strongly in favour 



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