WATER AND SODIUM CHLORIDE 37 



abstracting sodium and chlorine from the tissues. Hence the tissues, 

 in consequence of a vegetable diet, are robbed of sodium chloride. 

 They experience salt-hunger, a want which finds psychological expres- 

 sion in an indefinable longing for things which taste salt. 



That the desire for salt which so many herbivorous animals experi- 

 ence is really attributable to the nature of their diet is remarkably 

 illustrated by the habits of various human races. Von Bunge has 

 collected together by exhaustive inquiries from travellers, explorers, 

 and works of travel, a quantity of information regarding the consump- 

 tion of salt among different peoples. Only to cite a few among very 

 numerous instances: Country people, in Europe at all events where 

 habits have become fixed by centuries of adherence to the soil, eat 

 more vegetables and less animal food than the dwellers in cities. For 

 instance in France, where the collection of internal revenue upon salt 

 facilitates the acquirement of statistical data, it has been found that 

 the consumption of salt per head is three times as great in the country 

 districts as in the cities. Then there are whole tribes of nomads in 

 various parts of the world who are hunters, such as certain tribes of 

 the old North American Indians, some Arabian and Siberian tribes 

 and the Bushmen of South Africa. These people live, or used to live 

 exclusively upon a flesh-diet and they never taste salt. In fact, as a 

 rule, they find salt very disagreeable and consider the use of it by 

 Europeans ridiculous. Not only is this the case with tribes who have 

 lived for generations upon a flesh-diet, but it applies also to Europeans 

 who visit them and adopt their diet. Thus one traveller informed 

 von Bunge that while he lived among the Tunguses, an exclusively 

 carnivorous tribe which dwells in Siberia, he lived entirely upon 

 reindeer-flesh and game, and never experienced the slightest desire 

 for salt or inconvenience from the lack of it. 



Very different was the experience of the Scotch explorer, Mungo 

 Park, when travelling among the negro tribes of West Africa. These 

 people live upon a mixed diet containing a very high proportion of 

 vegetables. Salt is very rare in their country, and, as the vegetable 

 diet causes a longing for salt, Park states that among the natives, to 

 say that a man eats salt with his meals was equivalent to saying that 

 he was rich. In Park's own words: "In the districts of the interior 

 salt is the greatest of all delicacies. It strikes a European very strangely 

 to observe a child sucking a piece of rock-salt as if it were sugar. I 

 have frequently seen this done. I myself have found the scarcity of 

 this natural product very trying. Constant vegetable food causes a 

 painful longing for salt that is quite indescribable. On the coast of 

 Sierra Leone the desire for salt is so keen among the negroes that they 

 gave away wives, children, and everything that was dear to them, in 

 return for it." 



Hunting tribes, therefore, who subsist on flesh, experience no need 

 for salt and never eat it even when it is easy to obtain. Agricultural 

 tribes, on the contrary, experience a keen desire for salt. A peculiar 



