810 REPORT — 1894. 



distinctly into the optic thalamus, passing through the strise meduUares. They 

 could not be traced beyond this to the cortex. 



The author also gave a preliminary account of some experiments relating to the 

 antero-lateral tract of Gowers. He considers his researches so far show that it is a 

 crossed tract, consisting in the main of fibres proceeding to the middle lobe of the 

 cerebellum, but also containing a few scattered fibres proceeding from the posterior 

 roots, and apparently ending in the corpora quadrigemina. 



MONDAY, AUGUST 13. 

 The following Papers were read : — 

 1. On the Mechanical Theory of Lymiih Formation. By Dr. Starling. 



2. On Lymph Formation. By Walter S. Lazarus-Barlow, M.D. 



During the course of experiments performed in the Pathological Laboratory, 

 University of Cambridge, for the investigation of the pathology of the cedema 

 which accompanies passive congestion the author was led to examine certain of 

 the conditions that modify the flow of ]ymph in the normal animal. 



He introduced a cannula into one of the lymphatics of the hind limb of a dog, 

 and, as far as possible, ligatured all remaining lymphatics. The limb was then 

 emptied as completely as possible of lymph by rapid and firm squeezing from the 

 paw upwards, and an observation was immediately commenced upon the amount 

 of lymph formed in the limb during one hour. The animal was under A.O.E. 

 mixture and was kept absolutely at rest, excepting that coagulation of the lymph 

 in the cannula was prevented by occasional gentle squeezing of the limb. Imme- 

 diately before the expiry of the hour the limb was again emptied of lymph as 

 completely as possibly by firm squeezing. The lymph was collected in carefully 

 graduated tubes, and the amount thus obtained was regarded as the normal for 

 the individual. 



An elastic ligature previously arranged round the limb was then tightened to 

 such an extent as, it was known from other experiments, would raise the pressure 

 in the femoral vein from the normal 4-5 mm. of mercury to 25-35 mm. Exactly 

 the same processes were carried out during the collection of lymph under these 

 modified conditions as were described for the normal conditions. The duration of 

 increased pressure was one hour. Lastly, the elastic ligature was removed, and 

 the amount of lymph formed in an hour under normal conditions was again 

 estimated. 



The limb was therefore as free as possible from lymph immediately before 

 beginning and immediately before ending each of the three portions of the 

 investigation. 



The author found that the amounts collected in the three periods were either 

 absolutely identical, or that the amount collected during the period of high 

 venous pressure was less than that collected when the pressure was normal. On 

 no occasion did he find that an increase of venous pressure was accompanied by an 

 increase in the amount of lymph-flow. 



The amount of lymph-flow, however, being the product of two factors — viz. the 

 amount of fluid poured out by the blood-vessels and any modifications in that 

 amount introduced during the sojourn of the lymph in the tissues — it was necessary 

 before concluding that an increase of lymph-formation does not accompany an 

 increase in venous pressure to determine whether an excessive amount of fluid had 

 accumulated in the tissues in the form of oedema, since it was possible that the 

 increased venous pressure might have caused an increased outflow of fluid from 

 the capillaries and venules, and that that increased outflow might not have shown 



