134 KILBOURNE. 



chloride are found in the garrison ration, there are only 1.3 in that 

 of the Filipino troops, a remarkable difference. An average of 1.6517 

 grams was found in our third or beriberi-free group. 



An important influence of the potassium salts has been noted by 

 Bunge. 12 "If a potassium salt be in solution together with sodium 

 chloride, the two partially react on each other, with formation of potas- 

 sium chloride. If now potassium carbonate, for example, be eaten, the 

 same reaction occurs in the body: K 2 C0 3 -f 2NaCl^T2KCl+Na 2 C0 3 . 

 The kidney has the power of removing soluble substances which do not 

 belong to the blood, or are present in it to excess, and consequently the 

 two salts formed as above are excreted. Hence, potassium carbonate has 

 caused a direct loss of sodium and chlorine. For this reason, if potatoes 

 and vegetables rich in potassium salts are eaten, sodium chloride must 

 be added to the food to compensate for the loss. Natives living on rice 

 do not need salt, for here the potassium content is low. Tribes living 

 solely on meat or fish do not use salt, but caxe is taken that the animals 

 slaughtered for food shall not lose the blood rich in sodium salts, and 

 strips of meat dipped in blood are, by some races, considered a delicacy." 

 If. this be true, an excess of sodium salts will cause a loss of potassium 

 in the same manner. 



Jaques Loeb " has shown the necessity for a balance between the Na. Ca, and 

 K ions, and that the Ca and K ions counteract the effects of the Na ions in the 

 blood. When marine animals were placed in a pure solution of sodium chloride 

 of the same concentration as sea water, their muscular contractility was lost. 

 Small amounts of Ca and K ions antagonized the poisonous effects of the Na ions. 



Herter gives the daily amount of sodium chloride necessary for a man 

 as about 8 grams, which would be about 6.5 grams for a Filipino. 

 The average daily amount of table salt consumed by each man in the 

 organizations we investigated was 10 grams. This amount, ordinarily 

 not harmful, since most people consume quantities far in excess of the 

 physiological requirements, might be too much for diets as low in K ions 

 as are those of the Scouts. 



The amounts of calcium ingested were greatly in excess of their 

 physiological needs. 



The necessity of a proper balance in food salts is shown by the relation 

 of varying amounts of sodium chloride to the oedema of nephritis, and 

 of calcium chloride to epilepsy and rickets. 



A deficiency in the amounts of potassium and phosphorus, or a 

 disproportion between these elements and sodium, calcium and mag- 

 nesium, might well account for the production of beriberi. As in the 

 case of rickets and scurvy, because of the intricacy of the problems 

 involved, and the large part played by the selective powers of the body 



12 Physiologische Chemie. 3. ed. (1894), 108-116. 

 "Am. Journ. Phys. (1900), 3, 327. 



