84 



SCIENCE 



[N. S. Vol. LIII. No. 1361 



brane of a gland are oppositely cliarged. 

 Tinder such circumstances positively cliarged 

 water particles will be driven in the direction 

 from the positive to the negative side of the 

 membrane. As soon as the positively charged 

 water particle reaches the negative side of the 

 membrane it gives off its charge. This en- 

 ables other positively charged water particles 

 to follow. 



Ideas similar to those offered by Girard and 

 by Bernstein have been expressed by way of 

 explanation of other cases of abnormal 

 osmosis by Bartell and his collaborators, and 

 by Freundlich. 



Whatever the ultimate theory of the driv- 

 ing force in these cases may be, we have a 

 right to state that the electrification of the 

 particles of water migrating through a mem- 

 brane is a fact; that the sign of this electrifi- 

 cation seems to depend on the chemical na- 

 ture of the membrane in contact with water; 

 that the rate of migration of these charged 

 particles of water through the membrane from 

 the side of pure water to the side of the solu- 

 tion is accelerated by the ions of the opposite 

 sign of charge and retarded by the ions with 

 the same sign of charge as that of the water 

 with a force increasing with the valency of 

 the ion ; and that the relative acceleration and 

 retarding effects of the two oppositely charged 

 ions on the rate of diffusion of electrified 

 water are not the same for all concentrations, 

 that in lower concentrations of electrolytes 

 the accelerating action of the opj»ositely 

 charged ion increases at first more rapidly 

 than the retarding effect of the other ion; 

 while for higher concentrations the reverse 

 is the case, until finally a concentration of 

 the electrolyte is reached where the effects of 

 the oppositely charged ions more nearly bal- 

 ance each other. 



Jacques Loeb 



The Eockefellee Institute 

 roE Medical Eeseakch, 

 New Toek, N. Y. 



HENRY ANDREWS BUMSTEAD 



My personal acquaintance with Henry A. 

 Bumstead dates from a meeting of the British 



Association in Winnipeg in the summer of 

 1909. He had studied in Cambridge, England, 

 where his engaging personality, keen intelli- 

 gence, and unusual savoir faire had made him 

 a place in the hearts and homes of English 

 scientists which has been held by few Ameri- 

 cans. I was then almost unknown both to him 

 and to them, but I soon learned that if Bum- 

 stead was in any gathering I should at once 

 feel at home. 



I was walking with him one day through 

 one of the busy streets of Winnipeg when he 

 asked if I would not step into a shop with him 

 while he bought a little memento for Mrs. 

 Bumstead, a " bad habit " which he said he had 

 formed on trips away from home. 



I mention these two trivial incidents because 

 they reveal the soul and heart of the man; and 

 what, after all, is either science or art in com- 

 parison? 



When in 1917 the important and difficult 

 post of scientific attache in London was cre- 

 ated, Bumstead was the only man considered, 

 for no scientist in this country had his tact, 

 his judgment, his knowledge of England, and 

 his ability to assist in bringing about what was 

 then, and what is now, the most important need 

 of the modern world, namely, the cooperation 

 and mutual understanding of the two great 

 branches of the Anglo-Saxon race. 



Bumstead's success in London was extra- 

 ordinary. The British liked and trusted him. 

 Admiral Sims and our own War Department 

 placed large responsibilities upon him, and his 

 office became the center of a very active and 

 very important service. Young American 

 officers who went abroad on scientific missions 

 found him the center of their contacts and the 

 prime source of their usefulness. They all 

 became his devoted admirers. Not one or two 

 but a dozen or more of both British and Amer- 

 ican officers who came to Washington during 

 the war told me that they owed their success 

 in their work in England and the continent 

 primarily to Bumstead, and counted it the 

 most valuable part of their experience that 

 they had had an opportunity to become ac- 

 quainted with him. One of these officers de- 



