662 ABSORPTION. 



rary inconvenience; and, subsequently, three drachms of expired air, 

 without much temporary disturbance ; and M. Lepelletier 1 affirms, that 

 in the amphitheatre of the Ecole Pratique of Paris, in the presence of 

 upwards of two hundred students, he injected thrice into the femoral 

 vein of a dog, of middle size, at a minute's interval, three cubic inches 

 of air, without observing any other effect than struggling, whining, 

 and rapid movements of deglutition ; and these phenomena existed only 

 whilst the injection was going on. Since that he has often repeated 

 the experiment with -identical results, " proving," he observes, " that 

 the deadly action of the air is, in such case, mechanical, and it is pos- 

 sible to prevent the fatal effects by injecting it so gradually, that the 

 blood has power to disseminate, and perhaps even to dissolve it with 

 sufficient promptitude to prevent its accumulation in the cardiac cavi- 

 ties." From the experiments of Mr. Erichsen, however, the cause of 

 death in such cases, would appear to be asphyxia. 



As liquids are frequently passed off by the urinary organs soon after 

 they have been swallowed, it has been believed by some, either that 

 there are vessels which form a direct communication between the sto- 

 mach and bladder ; or that a transudation takes place through the 

 parietes of the stomach and intestine, and that the fluids proceed 

 through the intermediate areolar tissue to the bladder. Both these 

 views, we shall hereafter show, are devoid of foundation. 



In animals, in which the cutis vera is exposed, or the cuticle very 

 thin, nutritive absorption is effected through that envelope. In the 

 polypi, medusae, radiaria, and vermes, absorption is active, and accord- 

 ing to Zeder and Rudolphi, 2 entozoa, that live in the midst of animal 

 humours, imbibe them through the skin. A few years ago, Jacobson 3 

 instituted experiments on the absorbing power of the helix of the vine 

 (Limagon des vignes). A solution of prussiate of potassa was poured 

 over the body. This was rapidly absorbed, and entered the mass of 

 blood in such quantity, that the animal acquired a deep blue colour 

 when sulphate of iron was thrown upon it. In the frog, toad, sala- 

 mander, &c., cutaneous absorption is so considerable, that occasionally 

 the weight of water, taken in this way, is equal to that of the whole 

 body. We shall see, hereafter, that the nutrition of the ftetus in utero 

 is mainly, perhaps, accomplished by nutritive absorption effected through 

 the cutaneous envelope. 



II. ABSORPTION OF LYMPH OR LYMPHOSIS. 



This function is effected by agents, that strongly resemble those con- 

 cerned in the absorption of chyle. One part of the vascular apparatus 

 is, indeed, common to both, the thoracic duct. We are much less 

 acquainted, however, with the physiology of lymphatic, than of chy- 

 liferous, absorption. 



1 Physiologie Medicate et Philosophique, i. 494, Paris, 1831. 



2 Entozoorum Histor., i. 252, 275, Berlin, 1829. 



3 Memoir, de TAcad. des Sciences de Berlin, 1825, and Tiedemann, Traite Complet de 

 Physiologie de 1'Homme, edit. Fr.,p. 242, Paris, 1831. 



