8 GENERAL AND PHYSICO-CHEMICAL. 



tomic alcohol), passes slowly, and glycerin (triatomic) also passes slowly, 

 but faster than erythrite. Ethylene glycol (diatomic alcohol) passes rather 

 rapidly, and the monatomic alcohols immediately divide themselves 

 equally in the serum and blood corpuscles. Ether, esters, aldehyde, 

 and acetone divide themselves so that the blood corpuscles contain more 

 than does an equal volume of serum. These bodies are equally absorbed 

 by the blood corpuscles. Ammonium salts with univalent anions pass 

 in quickly while with divalent or polyvalent anions the greater part 

 remains in the serum; still they pass in to a greater extent than do the 

 corresponding salts of the fixed alkalies. 



OVERTON had previously arrived at the same results, using plant 

 cells and chiefly by making use of the plasmolytic method. Urea is prob- 

 ably more quickly taken up by the blood corpuscles than by plant cells, 

 and ammonium salts also seem to pass more easily into the blood cor- 

 puscles than into the plant cells. 



In regard to other salts HEDIN'S results have been substantiated 

 by OKER-BLOM, 1 by estimating the electrical conductivity of the blood. 



It must also be stated that according to HEDIN, only those bodies 

 which do not pass, or pass slowly into the cells, can essentially alter 

 the volume of the cells. A close correspondence exists in this regard 

 between the plant and animal cells. 



GURBER found that when blood corpuscles are repeatedly washed 

 with salt solution until the wash solution does not show any alkaline 

 reaction, and are then suspended in NaCl solution and treated with 

 C(>2, the alkaline reaction increased while the blood corpuscles became 

 richer in chlorine. No exchange of K or Na took place. 2 GURBER 

 explains the experiment as follows: the carbonic acid set a small amount 

 of HC1 free from the salt, and this HC1 was taken up by the blood corpuscles. 

 The Na2COs formed at the same time gave the alkaline reaction to the 

 solution. KoEPPE 3 as well as HAMBURGER and v. LiER 4 claim, on the 

 contrary, that an exchange of HCOa-ions and Cl-ions takes place between 

 the blood corpuscles and the solution, and HAMBURGER and v. LIER 

 claim to have shown that the blood corpuscles are permeable only for 

 anions, while the cations do not pass in. 



HAMBURGER 5 and his collaborators have also found about the same 

 osmotic, phenomena with other free mobile cells such as leucocytes, 

 spermatozoa as with the red blood corpuscles. The osmotic relations 

 have also been tried with intact parts of organs, therefore with cells 



1 Pfliiger's Arch., 81, 167 (1900). 



2 Sitzungsber. d. med. phys. Gesellsch. zu Wiirzburg, 1895. 

 Pfluger's Arch., 67, 189 (1897). 



4 Arch. f. (Anat. u.) Physiol., 1902; 492. 



* Osmotischer Druck und lonenlehre, Wiesbaden, 1902, 1, 401. 



