SALTS. 81 



sodium chlorid subserves is in connection with the process 

 known as " osmosis," or the diffusion of liquids' through animal 

 membranes, a subject which will be discussed in connection 

 with the process of absorption. A second office which it pos- 

 sesses is to hold in solution the globulins. TJie globulins are 

 proteids which are not soluble in distilled water, as are the native 

 albumins, but are soluble in dilute solutions of sodium chlorid 

 (1 per cent.). The so-called " normal" or " physiologic" salt-solu- 

 tion is made by dissolving 6 grams of sodium chlorid in a liter of 

 water. The importance of this office of common salt will be 

 more fully appreciated in the study of the plasma of the blood, 

 of which the globulins form an essential part. A third office 

 which is attributable to it is to aid in the excretion of waste 

 matter. The sodium chlorid of the blood is the source of the 

 hydrochloric acid of the gastric juice. 



Source of Sodium Chlorid. The food taken into the body is 

 the principal source of the sodium chlorid which the body con- 

 tains. 



The quantity (percentage) of this salt in some articles of food 

 is as follows : 



Oats 0.01 



Turnip 0.03 



Potato 0.04 



Cabbage 0.04 



Beet 0.06 



It has been the opinion of physiologists that sodium chlorid 

 is not present in sufficient amount in human food to satisfy the 

 demands of the body ; consequently, that an additional amount 

 must be taken in as a condiment at the table or be added to 

 the food during the process of cooking. But Dr. F. A. Cook, 

 surgeon to the first Peary North-Greenland Expedition, states 

 that the Eskimos who dwell between the seventy-sixth and 

 seventy-ninth parallels use no salt or condiment of any kind in 

 their food, which is entirely of meat and blubber only one-third 

 cooked. This cooking is done in order that there may be obtained 

 the blood of the meat, and this blood the Eskimos drink. How- 

 ever this may be with the Eskimos, it is the general experience 

 that by the addition of salt the food is not only made more pala- 

 table, but the digestive juices are also increased and digestion im- 

 proved. This insufficiency of salt in the food of man is seen also 

 in that of some of the lower animals. While carnivora or flesh- 

 eating animals find in their food all the salt they need, it is differ- 

 ent with the herbivora or vegetable-eaters. Especially noticeable 

 is this fact in the ruminants. Boussingault many years ago demon- 

 strated this by a series of experiments which he conducted. He 

 selected two sets of bullocks as nearly as possible in the same 

 condition of health, and to both sets he gave the same food, except 



