CHAPTER XI. 



AN EXAMINATION OF THE OPINION WHETHER SOME OF THE 

 LYMPHATIC VESSELS MAJ NOT BE CONTINUATIONS OF THE 

 SMALL ARTERIES. 



I HAVE already observed that, soon after the discovery of 

 the lymphatic vessels, Glisson and others suspected that they 

 arose from the cavities of the body to take UJD the fluids ex- 

 haled from the blood-vessels ; but, at the same time, another 

 opinion was entertained by some anatomists, namely, that a 

 part of the lymphatics were reflected from the small arteries to 

 which they corresponded, in the same manner* as the common 

 veins belong to the arteries carrying red blood. 



In this opinion, that the lymphatics were only veins, anato- 

 mists were confirmed from experiments made by injections, 

 particularly the blowing air into the arteries of the kidney, 

 spleen, &c., and seeing it return by the lymphatics ; 1 a fact 

 that has since been proved to be owing to the air having burst 

 from the arteries into the cellular membrane, and so having got 

 into these vessels, and therefore by no means proving a direct 

 communication between those arteries and the lymphatics. 2 



Other injections, likewise, such as mercury, water, &c., hav- 

 ing been thrown into arteries, and afterwards having got into 

 the lymphatics, have been mentioned as so many proofs of a 

 direct communication ; but greater experience with injections 

 has convinced some of the more accurate amongst later anato- 

 mists of there likewise being a fallacy in these experiments ; 

 or of the fluids having got from the arteries into the lympha- 

 tics, not by passages which were natural to the living body, 

 but by such as were the eifects of laceration in the dead one. 



1 Nuck, Adenog. cap. iv, vi. 



2 See Professor Monro, De Venis Lymph. Valvul. 



