rv] of Glands and Tissues. 115 



"composed of these two factors, namely, the glandular acini, 

 " and the different terminations of the vessels. Wherefore in 

 "order that some common result may issue from this, some 

 "intercourse between the glandular elements and the vessels 

 " must necessarily take place. 



"Moreover, in the liver Nature follows this rule that the 

 "branches of the vena portas play the part of arteries, as is 

 "indicated by the complexity of their coats; and so closely 

 "is the vena portae associated and connected with the bile- 

 "duct that the small divisions of both of them are closely 

 "wrapped together in the same sheath." 



He concludes that both observation and reason shew that 

 the liver is to be regarded as a conglomerate gland, such as is 

 the pancreas. And "since it is a feature of conglomerate 

 "glands that they possess an excretory vessel of their own," 

 as Sylvius and Steno have shewn, " since this is the rule of 

 " nature in the parotid, in the pancreas, in the salivary glands, 

 " the sweat glands, the lacrymal glands and others, since in 

 11 these dispersed through their proper substance there may be 

 " seen a special vessel distinct from the other ordinary vessels, 

 " such as veins, arteries and nerves, a similar structure must be 

 11 looked for in the liver." He infers that the bile-duct is the 

 proper excretory duct of the liver. 



He had to contend against a heresy recently put forth that 

 the bile was secreted, not in the liver itself but in the gall- 

 bladder by means of the blood vessels and membranes of that 

 organ, and that it was carried thence to the liver to aid in the 

 process of sanguification. Against such a view all the above 

 anatomical results afforded irresistible arguments; but he 

 clenched these by a vivisectional experiment. Laying open 

 a kitten, he tied the common bile-duct close to its entrance 

 into the duodenum, and by a median incision emptied the gall- 

 bladder. In a short time the common duct and the bile-duct 

 were filled with bile. He then put a ligature round the neck 

 of the gall-bladder ; the common duct and the bile-duct were 

 still full of bile, and when with his finger he tried to press 

 back their contents towards the liver, they returned with force 

 when the finger was removed. 



8—2 



