290 Mageridie on Absorption. 



placed in contact ; these operations are not performed with- 

 out discernment; they are done with the nicest sense of 

 discrimination ; those organs choose with great exactness 

 what ought to be taken in and what rejected ; and it is not 

 until after due examination that they determine to exercise 

 their absorbing power. 



It is sufficient merely to doubt of the truth of such expla- 

 nations to become at once sensible of their absurdity ; but 

 they seldom produce this effect. Such is the charm which 

 they exercise over our minds that we are easily led to be- 

 lieve them true ; and we afterwards repel with passion what- 

 ever might tend to undeceive us.* It is, however, time 

 that such deceptions should disappear from the doctrine of 

 Physiology. 



I believe I do not exaggerate in asserting that hitherto, 

 nothing positive has been advanced relative to the mechan- 

 ism by which absorption is effected in animals of red and 

 warm blood. 



Some experiments which I have made this year seem to 

 me to throw some light on this important subject ; when I 

 shall have related the circumstances, the judgment of the 

 Academy will show me whether I am mistaken, or whether 

 I have hit upon the truth. 



In a public lecture on the mode of action, of medicines, I 

 was showing the effect of a certain quantity of water, at the 

 temperature of 40*^ Centigrade, (104° Farenheit) introdu- 

 ced into the veins; in making this experiment, the idea 

 struck me to observe the effect of the artificial plethora thus 

 produced, on the absorbent faculties ; consequently, after 

 having injected nearly a litre (almost an Enghsh quart) of 

 water, into the veins of a dog of a middling size, I introdu- 

 ced into the pleura a small dose of a substance, the effects 

 of which were well known to me. It struck me as singular 

 that those effects did not appear until several minutes after 

 the time in which they are ordinarily seen. I immediately 

 repeated the experiment on another animal, and obtained a 

 similar result. 



In several other essays the effects were observable at the 

 time when they should manifest themselves, but they were 



* At least in the present state, and with the absurd system of education in 

 which we are brought up. 



i 



