FOOD AND WATER, STIMULANTS, ETC. 



77 



CHAPTER VI. 



FOOD AND WATER, STIMULANTS AND 

 NARCOTICS. 



SECTION I. 1, By food we mean all substances that 

 we eat or drink to satisfy hunger and nourish the hody. 



2. If we have to repair any manufactured article, we 

 use the same kinds of material that the article was made 

 of. We repair a harness with leather, a stove with iron, 

 a table with wood. So our food, which repairs the body, 

 must contain the same substances that the body contains. 



3, Analysis by the chemist shows that the body of man 

 consists of fifteen substances, called elements. 1 



Elements. Parts in 100. 



Oxygen 72. 



Hydrogen 9.1 



Nitrogen 2.5 



Chlorine 085 



Fluorine 08 



Carbon 13.5 



Phosphorus 1.15 



Calcium . 1.3 



Elements. Parts in 100. 



Sulphur 1476 



Sodium 1 



Potassium 026 



Iron 01 



Magnesium 0012 



Silicon 0002 



Manganese A trace. 



4, Our food must contain every one of the above ele- 

 ments. Of some, the body contains little ; and we require 



1 These substances are not always in exactly the proportions given in 

 the table. Each would differ in amount in different bodies, and in the 

 same body at different times. 



