INORGANIC FOOD-STUFFS. 85 



mens; (2) jelly-forming substances; (3) fatty or oily 

 matters; (4) sugars; (5) starch. The albumens are the 

 most important. A man can maintain life on water and 

 lean meat, while if he should get, along with plenty of 

 water, all the fat and sugar and arrowroot (which is 

 nearly pure starch) that he could eat, he would slowly 

 starve. 



The reason of this is very simple. A special substance, 

 named nitrogen, is essential for the making or repairing 

 of all the organs of the body. Albumens contain some 

 of this substance; fat, starch, and sugar do not. Every 

 day some nitrogen is carried away from the body in its 

 waste matters. If none of it be supplied -in the food, a 

 man will therefore slowly die of nitrogen-starvation, no 

 matter what abundance he may have of other things. 



Crackers and cheese would be useless to a man dying 

 of thirst; so fat or sugar or starch would be useless to a 

 man whose organs were starving for nitrogen. 



10. Inorganic Food-Stuffs. A sufficient quantity of 

 most of these is contained in bread and meat and milk 

 and our other common foods. Thus iron is an essential 

 part of the blood, but in health we need no more than 

 is contained in the vegetables and meat which we eat 

 daily. 



Water and common salt are the only inorganic food- 

 stuffs that are usually taken by themselves or specially 

 added to our food in cooking. The body daily gives 

 off more of each than it would otherwise receive. 



Which are the most important? How do we know that the others 

 are less valuable ? Explain why starch and fat cannot take the place 

 of albumens in nourishing the body. Illustrate. 



10. How are we supplied with most inorganic food-stuffs in suffi- 

 cient quantity ? Illustrate. How are water and common salt excep- 

 tional ? Why ? 



