732 



SCIENCE. 



[N. S. Vol. XVII. No. 436. 



paper. By this method we can arrive at 

 the exact relative physiological efficiency 

 of the different positive ions, and, so far 

 ias I have gone, it corresponds closely with 

 the chemical or catalytic action of these 

 ions. 



The addition to sodium chloride of any 

 salt of which the anion overbalances more 

 than chlorine does over sodium should not 

 neutralize the poisonous or stimulating ac- 

 tion of sodium chloride, but should increase 

 the latter. This is the case : The addition 

 of barium salts, or of sodium sulphate, 

 phosphate, citrate or ammonium citrate in- 

 creases the stimulating action of sodium 

 chloride. 



6. If sodium chloride is poisonous be- 

 cause the chlorine predominates, we should 

 be able to neutralize its poisonous action 

 by predominant positive ion salts, but not 

 by predominant negative ion salts. This is 

 the case so far as observations go : The ad- 

 dition to sodium chloride of small amounts 

 of calcium chloride, as found by Howell, 

 or potassium or lithium, will greatly pro- 

 long the life of the nerve immersed in the 

 solution. The toxic and antitoxic action, 

 so far as the nerve is concerned, and I be- 

 lieve in other cases also, is thus shown to 

 be due to a neutralization of a predominant 

 ion by an ion of an opposite charge, and is 

 not due to any antitoxic action between 

 monovalent and divalent positive ions. The 

 stimulating action of the sulphate or cit- 

 rates can not be referred primarily in my 

 opinion to their precipitation of calcium 

 or rendering it inert. The stimulating 

 action of these salts may be neutralized, 

 for example, by potassium where there is 

 no question of precipitation. The antago- 

 nistic action is thus shown to be due prob- 

 ably not to a combination between the toxin 

 and antitoxin, but to the fact that each of 

 these acts on the protoplasm, but in an 

 opposite manner. 



7. The theory that positive ions act like 

 the anesthetics and depress protoplasmic 

 activity or inhibit has been confirmed by 

 observations on the eggs of echinoderms. 

 The antesthetics liquefy these eggs; lique- 

 faction is also caused by the electric cur- 

 rent on the anode side. These results were 

 obtained by Mr. 0. H. Brown. Further 

 analogies of action were observed by Dr. 

 Spaulding and will be published shortly. 

 Preliminary experiments on the nerve in- 

 dicates that this resemblance extends pos- 

 sibly to protoplasmic respiration, salts of 

 a predominant positive ion checking respi- 

 ration while those of predominant nega- 

 tive ion increase respiration, at least tem- 

 porarily. My experiments are, however, 

 still too few to enable positive statements 

 to be made. 



8. The current of rest of motor nerves 

 shows marked fluctuations if the tip of the 

 nerve is dipped into acids, alkalies or salt 

 solutions. The acids quickly depress the 

 current, alkaline salts increase it. The 

 current may thus be many times abolished 

 by acids and reappear on dipping in 

 sodium hydrate. These results are be- 

 ing carried further. They indicate the 

 general truth of the conclusions of the op- 

 posite physiological action of anions and 

 eathions. 



9. The results recorded of the antago- 

 nistic physiological action of the anions and 

 eathions hold also for the central nervous 

 system and for the kidneys. This work 

 has been done by Dr. S. A. Matthews and 

 Mr. 0. H. Brown and others in this labo- 

 ratory and will be shortly published. They 

 show that the motor nerve is not unique, 

 but that its reaction corresponds to those 

 of many other tissues. 



I believe that the exceptions observed by 

 Loeb in muscle may be explained in part 

 by the fact that when a muscle is put into 

 a salt solution it is impossible to state 



