WATER. 45 



oxygen upon the tissues and the calorific elements of the food, may 

 be regarded as established; and to prevent an undue accumulation 

 of it in the blood from these sources is the principal object of the 

 aerating process. 



5. Protoxide of Hydrogen Water. (HO.) 



Water enters into the composition of every fluid and every 

 tissue, however solid (even enamel), in the body, uniting in true 

 binary combination, and forming one of its essential constituent 

 parts. It is, therefore, one of the most important of the immediate 

 principles, and exists in far greater amount than all the rest to- 

 gether. 



The cubical mass of the human body is calculated by Eobin and 

 Yerdeil as varying from 62 to 70 litres 1 in the male, and from 46 to 

 53 in the female equal in the former to a cube 16 to 16.4 inches on 

 a side. Of the preceding quantity, at least 42 or 43 litres are water, 

 which equals a cubic mass 14.4 to 15.2 inches on a side. Thus 

 nearly three-fourths of the body is water. Burdach estimated the 

 water at two-thirds of its weight. Of course the proportion is still 

 greater in infancy and childhood. 



A. table is given by the authors just mentioned, 2 showing the 

 proportional amount of water in each fluid, and in each tissue and 

 organ, in the body. With the exception, of enamel, dried cuticle, 

 teeth, bones, tendons, and elastic tissue, there is no tissue which is 

 not more than one-half water. Enamel is only ^^ water (Senae) ; 

 the substance of the testis, T 8 8 7 5 water. The human brain is T 7 8 9 D - 

 water. (Denis.) But no tissue or fluid in the body has always pre- 

 cisely the same amount of water, or of any other immediate principle. 

 It varies constantly, though within narrow limits, from one- tenth to 

 three-tenths, and the mean only is given in the table alluded to. 



But the other immediate principles vary with the variations in 

 the water. Hence the error of those who would find the cause of 

 diseases in one tissue or fluid alone, or who would cure them by the 

 administration of water alone, or of any other immediate principle 

 exclusively. 



In all the tissues and organs just mentioned, in which less than 

 one-half is water, and in many cases where the water constitutes 

 T 7 7 (muscle) to T 8 5 (cortical substance of calf's brain) of the whole, 



1 A litre is very nearly a quart in measure. * Op. cit., pp. 115-118. 



