%%2t Magendie on Ahsorpiion. 



the distention of tlie blood vessels that the diminution oi' 

 total want of absorption must be attributed. 



From that moment I became, as it were, completely mas- 

 ter of the phenomenon, which, until then, had been to me 

 an impenetrable mystery. Being now able to produce or 

 prevent its developement, to render it prompt or tardy, in- 

 tense or feeble, at pleasure, it was difficult that its nature 

 should entirely escape my investigation. 



In reflecting on the constancy and the regularity of the 

 phenomenon, it seemed to me impossible to connect it with 

 what the physiologists term vital action, such as the action 

 of the nerves, the contraction of the muscles, the secretion 

 of the glands, &;c. It was much more reasonable to com- 

 pare it with some physical effects : and among the conjec- 

 tures that may be permitted on the subject, that which 

 would make absorption depend on the capillary attraction of 

 the vascular membranes on the absorbed matter, was un- 

 doubtedly the most probable ; this supposition agrees per- 

 fectly with all the facts observed. For, if we suppose this 

 cause to preside over the absorption, solid substances insol- 

 uble in our humours, being unable to traverse the mem- 

 branes of the small vessels, should resist absorption, which 

 is exactly the case : solids which, on the contrary, are capa- 

 ble of combining whh our system, or of dissolving in the 

 blood, would be susceptible of being absorbed, which is al- 

 so conformable to observations. The greater number of 

 liquids, whatever be their chemical natures, being capable 

 of wetting, or being promptly imbibed by the vascular 

 membranes, should be rapidly absorbed, this conclusion is 

 confirmed by experience, even with the caustic liquids. In 

 this hypothesis, the greater the distention of the vessels the 

 less marked would be the absorbing power, and the mo- 

 ment might arrive when that power would be no longer seii- 



aud impalpable powder, suspended in water, and which causes immediate 

 death if it be injected into the jugular vein, because it obstructs the last di- 

 visions of the pulmonary artery. (See Vol. I. of my Elementary treatise 

 of Physiology.) Not having: siiceeded in the introduction of oil, I had re- 

 course to a slight solution of gum-drag-on, which produced exactly the same 

 effect as the oil. After these trials I contented myself with injecting water 

 after having withdrawn the blood. These facts show how important it is 

 that every thing which enters into circulation with the blood, should arrive 

 there in exceeding small particles, and after being, as it were, strained 

 through the agents of absorption. This use ol" the absorbing oi-gans had 

 not, I believe, been heretofore observed. 



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