368 FACTS RELATING TO CUTANEOUS ABSORPTION. 



who chose it for the subject of their inaugural theses ; namely, Drs. Rous- 

 seau, Klapp, Daingerfield, Mussey, and J. Bradner Stewart. 



The three first of these gentlemen state that when spirit of turpentine, and 

 several other substances which are commonly supposed to be absorbed by the 

 skin, were applied to it in a way which prevented their volatile parts from 

 entering the lungs by respiration, no absorption took place. But when the 

 inspired air was impregnated with exhalations from these substances, they 

 perceived satisfactory proofs that the exhalations entered the system. From 

 these facts they inferred that when those articles entered the body by absorp- 

 tion, they were taken in by the lungs, and not by the external surface. 



On the other hand, the two gentlemen last mentioned, state that after immers- 

 ing themselves in a bath consisting of a decoction of rhubarb, of madder, 

 or of turmeric, their urine became tinged with these substances. They also 

 assert that the coloring matter of these different articles is not volatile ; and, 

 therefore, could not have entered the lungs during the experiments.* 



The statement in page 301, from Dr. Soemmering, that when mercury is in- 

 jected backwards in the absorbent vessels which originate on the foot, it will 

 sometimes appear in small globules on the skin of the foot, has an important 

 connexion with this subject.f 



About the middle of the last century, it was generally believed by anatomists 

 that absorption was performed by the veins. This doctrine seemed to be 

 established by the experiments of Kaaw Boerhaave, which are related with 

 many other interesting statements, in his work, entitled " Perspiratio Dicta 

 Hippocrati," &c., published at Leyden, in 1738. In these experiments it 

 appeared to the author, that when the stomach of a dog was emptied of its 

 contents, and filled with warm water, immediately after death, the water 

 passed into the minute ramifications of the veins of the stomach, and from 

 them to the vena portarum, and ultimately to the heart in large quantities. 



This account appears to be disproved by some experiments of the late John 

 Hunter, made about twenty years after, and published in the Medical Com- 

 mentaries of Dr. William Hunter, part I. Mr. Hunter's experiments have 

 been considered as establishing the fact, that absorption, (in the intestines at 

 least,) is performed exclusively by the lacteals, or proper absorbent vessels, 

 and not at all by the veins. Kaaw Boerhaave is of course supposed to 

 have been mistaken ; and Mascagni, who has repeated his experiments, 

 refers the appearance of water in the veins to transudations through the coats 

 of the intestines ; which he has observed to take place in a great degree. 



In the year 1809, a memoir was presented to the national institute of France 

 by Messrs. Magendie and Delile, which contains an account of some experi- 

 ments that have an important relation to the above mentioned subject.^ 



* The Thesis of Dr. Rousseau was published in 1800. Those of Drs. Klapp and Dainger- 

 field in 1805. Dr. Mussey published in the Third Supplement to the Medical and Physical 

 Journal of Dr. Barton in 1809. Dr. Stewart published in 1810. Additional Observations by 

 Drs. Klapp, Rousseau and Smith, are published in the Philadelphia Medical Museum, vol. i. 

 new series. 



t Since the publication of the first volume the author has enjoyed the advantage of con- 

 sulting a translation, in manuscript, of some parts of the German edition of Dr. Soemmer- 

 ing's valuable work on the Structure of the Human Body. 



I The title of the paper is a " Memoir on the Organs of Absorption in Mammiferous Ani- 

 mals." A translation of it was published in the Medical and Philosophical Register of New 

 York, and in several other periodical works. 



