476 



Drs. Herring and Simpson. Relation of the [May 31, 



Watery solutions of Prussian blue have been extensively used ; they have 

 the fatal property of diffusibility. Carter (14) urged this objection to 

 the use of Prussian blue. It is, moreover, readily decolourised by the tissues, 

 and although the colour can be restored, it is, as Carter pointed out, both 

 soluble and diffusible in its colourless condition. 



Kisselew and Eeinke alone of all who have worked on the subject have 

 described endothelial cells lining the clefts between intralobular blood- 

 vessels and liver cells. No one else has been able to find them. - ■ Hering 

 denied the existence of natural clefts in this situation in the rabbit's liver, but 

 allowed that they might be produced artificially. 



Methods Used in the Present Inquiry and Results Obtained. 



The observations of the brothers Fraser, Nauwerck, Browicz, and Schafer, 

 and the results of our own experiments on injection of the liver cells from the 

 blood-vessels, are against the probability of there being perivascular lymphatics 

 in the lobules of the liver, but are not conclusive in themselves. We have 

 injected the lymphatics of the liver to ascertain if we could get the injection 

 mass to run into the clefts described by MacGillavry. 



The animals experimented on were dogs and cats. The injection mass 

 used was carmine gelatine prepared as already described for injection of the 

 blood-vessels. Carmine gelatine is pre-eminently suitable for this purpose 

 on account of its lack of diffusibility, the readiness with which it is solidified 

 and fixed without damage to the surrounding tissues, and the ease with which 

 the smallest amount can be detected. The main lymphatic trunks coming 

 from the portal fissure were clamped immediately after death ; they soon 

 become distended with lymph. One of the larger trunks close to the liver was 

 selected, and a thread passed round it by means of a needle, care being taken 

 not to injure any neighbouring trunks or the portal vein. It was then opened, 

 and a fine cannula, connected to the injection bottle and filled with carmine 

 gelatine, was inserted and tied in position. The liver was disturbed as little 

 as possible. The whole animal being immersed in a bath of water at 

 the temperature of the body, the pressure was gradually raised until the 

 carmine gelatine began to distend the lymphatic vessel. The pressure was 

 maintained for from one to three hours. In most cases the inferior vena cava 

 was opened above the diaphragm to prevent any rise of pressure in the blood- 

 vessels. When the experiment was completed the liver was removed from 

 the body, the clamp on the efferent lymphatic vessels being still attached ; 

 the tube which conducted the injection mass to the lymphatics was ligatured 

 close to the cannula. These precautions were adopted to prevent any escape 

 of injection fluid from the lymphatics. The liver was at once placed in 



