52 * Royal Society. 



different ways. By Hisinger, by Berzelius, and by Faraday it has 

 been ascribed to the liberation of hydrogen in this process : Davy and 

 others considered it as resulting directly from the attraction of the 

 metal to the negative pole : and Daniell conceives that the metal [so- 

 lution?] is directly electrolysed by the action of the voltaic circuit. 

 The author found that the ends of copper wires, placed in a solution 

 of sulphate of copper between two platina poles in the circuit, mani- 

 fest electric polarity ; so that while one end is dissolving, the other 

 is receiving deposits of copper : he also found that platina was, in 

 like manner, susceptible of polarity, although in a much less degree 

 than copper, when placed in similar circumstances. With a view to 

 determine the influence of nascent hydrogen in the voltaic reduc- 

 tion of metals, he impregnated pieces of coke and of porous char- 

 coal with hydrogen, by placing them, while in contact with a metal, 

 in an acid solution, when they thus constituted the negative pole of 

 the circuit ; and he found that the pieces thus charged readily re- 

 duced the metals of solutions into which they were immersed ; and 

 thence infers that the hydrogen is the agent in these reductions. 

 From another set of experiments he concludes, that during these de- 

 compositions, water is really formed at the negative pole ; a circum- 

 stance which he conceives is the chief source of the difficulties ex- 

 perienced in electro-metallurgic operations when they are conducted 

 on a large scale, but which may be avoided by a particular mode of 

 arranging the elements of the circuit so as to ensure the uniform 

 diffusion of the salt. 



The author obtained the immediate reduction of gold, platina, 

 palladium, copper, silver and tin from their solutions by the agency 

 of hydrogen contained in a tube, with a piece of platinized platina in 

 contact with the metallic salt : nitric acid and persalts of iron, on the 

 other hand, yielded their oxygen by the influence of the same agent. 



The general conclusion which he deduces from his experiments is 

 that, when a metallic solution is subjected to voltaic action, water is 

 decomposed, its oxygen passing in one direction, and its hydrogen in 

 the opposite direction ; the latter element performing at the moment 

 of its evolution at the negative pole the same part with respect to a 

 solution of sulphate of copper, that a plate of iron or zinc would per- 

 form to the same solution. 



March 16. — The following papers were read, viz. — 



1. " On the import and office of the Lymphatic Vessels." By 

 Robert Willis, M.D. Communicated by John Bostock, M.D., F.R.S. 



That absorption is the special office of the lymphatic vessels was, 

 until very lately, a universally received doctrine in physiology : but 

 it is now admitted that if they exercise this faculty, it can be only to 

 an inconsiderable extent ; and physiologists of high authority have 

 even denied that they possess any absorbing power at all. This 

 last is the opinion of Magendie, in which the author concurs. So lately 

 as 184-1, Rudolph Wagner asserted that "neither anatomical nor 

 physiological considerations render any satisfactory account of the 

 import and office of the lymphatics," which thus, shorn of their 

 ancient office, were repudiated as a superfluous apparatus in the 



