TENSION PHENOMENA OF LIVING ELEMENTS. 



tlu-n set free H + and HCOs~ ions, thus increa-in- the ionization 

 and therefore reducing the number of undissociated molecules, 

 which can escape. 1 



Since Osterhout showed that certain electrolytes may alter 

 the permeability of cells, we might expect to find, on the membrane 

 hypothesis, an effect of salts on the electric polarization of 

 imi-rle. H ober 2 observed that a portion of the surface of a 

 mu-cle treated with certain salts, KC1 for instance, becomes 

 i -1. iro-nriMtive (more permeable to anions) whereas a portion 

 n-l \\ith Nal or LiCl becomes positive (still less permeable 

 i" anions than is the normal unstimulated muscle). The order 

 of eite< ii\ i ness of the ions is as follows: Li<Xa<Cs<XHj< Kb 

 <K ,m<l ( \S<NO 3 < I< Br<Cl <valerianate, bui\rate, pro- 

 pioiiai' ate, formate <SO4, tartrate. Similar ionic series 



\\en- found by Overtoil, K. l.illie, Schwartz, Mathews, C.nii/iur, 

 I loin i , and Mayer in the effect of salts on the function.il at ii\ iiy 

 of inii-( It , nerve and cilia, but the exact relation of tlu--e phe- 

 nomena to permeability is not understood in every case. Pure 

 -ohnioii^ of salts of alkali metals may "inhibit" inu-cle by in- 

 permeability, but salts of alkali earth metals art -aid 

 to "inhibit" by decreasing permeability. . Mayer says that the 

 effect of -.ills on cilia is the reverse of that of muscle, but the 

 relation (.f ihis to permeability is not known. Since ion- aiit-i i 

 tin .ition state of hydrophile colloids in the same or ex- 



actl\ n \ -i.-ed order, and the kation series is found in no other 

 knoun physico-chemical phenomena, it might be supposed th.it 

 tin semipermeable membranes of muscle are colloitl.il. 



It -i t-ni- probable that sugar solutions inhibit the artivity of 

 nniM le l.v increasing the permeability, but since -u-.ir i- not an 

 t K i trol\ tt thi> question cannot be tested by electric method-. 



A ne-ati\e variation of muscle may also be produced by the 



ailed "h.emolytic" substances, but i> inv\ t -r-ible, whereas 

 that produced by salts may be reversible. In this connection it 



1 RiMl'. Q. J. Exper. Physiol.. 1910, III., 171, suppo-< <1 ttio aninn to be i>n>t--in; 

 |II>\MAI-I H h.i- not been shown that proteids, or even aniino acids dilTu-r nut nn 

 stiniiil.ith.ti. I do not see that the speculation of Galcntti, Zeit.f. All gem. Physiol., 

 1907, \ 1 at all explanatory. 



r's Arch., 1910, CXXXI\'.. 311. 



