106 



CHEMICAL COMPONENTS OP THE HUMAN BODY. 



the use of very salt food which caused intense thirst, and only rose to 4.18 when 

 two ounces of salt had been taken an hour before, and two quarts of water had 

 been drunk in the interval. The quantity of salt in the blood in different dis- 

 eases, however, is liable to great variation ; and there can be little doubt that 

 this variation is intimately connected (though whether in the relation of cause 

 or in that of effect, we are scarcely yet entitled to surmise) with the histological 

 and other transformations of the components of the blood. 1 The proportion of 

 chloride of sodium differs greatly in the several tissues, and also at different 

 periods of the development of the same tissue. Thus in Muscle, according to En- 

 derlin, 100 parts of the ash left after incineration of ox-flesh yielded nearly 46 

 per cent, of the chlorides of sodium and potassium ; which, as this ash constitutes 

 4.23 per cent, of the dried flesh, would give 1.94 as the proportion of chloride 

 of sodium in 100 parts of the latter ; and reckoning this dried residue to con- 

 stitute 23 per cent, of the whole substance of the muscle (the remaining 77 

 parts being water), the proportion of chloride of sodium in the latter will be 

 0.44; these figures, as will be presently seen, bearing a remarkably close corre- 

 spondence to those which represent the proportion of chloride of sodium in the ash, 

 solid residue, and entire mass, of the 'Blood. Next to muscle, the largest percentage 

 of chloride of sodium seems to be contained in Cartilage; and this especially in the 

 temporary cartilages of the foetus, the proportion diminishing as the phosphate of 

 lime is deposited. The percentage of chloride of sodium contained in the ash of 

 the costal cartilage of an adult has been stated at 8.2, and in the laryngeal cartilage 

 at 11.2 ; but as the ash does not constitute above 3.4 per cent, of the entire 

 substance, the percentage of chloride of sodium in the latter is at most 0.38 

 of the whole, or less than that of blood and muscle. In Bone, only from 0.7 to 

 1.5 per cent, could be extracted from the ash. Besides the important uses of 

 common salt in the Blood which have been already adverted to, it serves the 

 important purpose of furnishing the hydrochloric acid required (by many 

 animals at least) for the gastric secretion ( 81); and it also furnishes the soda- 

 base for the alkaline phosphate, whose presence in the blood appears to serve a 

 most important purpose in the respiratory process ( 84). Moreover, there is 

 reason to think, from the experiments of Boussingault upon animals, as well as 

 from other considerations, that the presence of salt in the blood and excreted 

 fluids facilitates the deportation of excrementitious substances , from the body. 

 The proportion in which it occurs in the principal animal fluids is repre- 

 sented by the following table, constructed by Prof. Lehmann chiefly from his 

 own analyses : 



PERCENTAGE OF CHLORIDE OF SODIUM IN VARIOUS ANIMAL FLUIDS, THEIR SOLID RESIDUE, 



AND THEIR ASH. 



Human Blood 



Blood of Horse 



Chyle . ; 



Lymph (Nasse) 



Serum of the Bl 



Blood of the Cat (Nasse) 



Chyle (Nasse) 



Human Milk 



Saliva . 



Gastric Juice of Dog 



Human Bile 



Mucus (Nasse) 



Serum of Pus (Nasse) . 



Solid Residue. 



1.931 



2.750 



8.313 



8.246 



5.200 



2.826 



7.529 



0.726 

 12.988 

 12.753 



3.353 

 13.100 

 11.454 



Ash. 

 57.641 

 67.105 

 67.884 

 72.902 

 59.090 

 67.128 

 62.286 

 33.089 

 62.195 

 42.089 

 30.464 

 70.000 

 72.330 



1 The special influence of the saline constituents of the Blood upon its red corpuscles, 

 will be noticed hereafter (139). 



