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Taking the latter question first — what is food. Food in th^ 

 general sense may be taken to mean anything that is taken into 

 the digestive system of man or animals, either to satisfy hunger, 

 or to excite pleasurable sensations through the taste. In this 

 sense the term food is used in laws regarding adulteration ; food 

 in this case including drinks and condiments. The more scientific 

 or exact definition of food is that it is that which supplies material 

 for growth, replaces the waste of the body or furnishes the energy 

 by which the body performs its functions, or the work necessary 

 for its existence or mode of living. 



With regard to the functions of food probably the first thought 

 is that it is that which furnishes material for growth, increasing 

 the size or weight of the body. This, however, is not its chief or 

 most important function. In all living animals there is through 

 the mere act of living a waste of tissue. The involuntary action 

 of the muscles of the heart, whereby the blood is circulated ; the 

 almost involuntary action of the muscles which produce respira- 

 tion, can only take place through destruction breaking down or 

 change of composition of the tissues. No man, however lazy, carr 

 live without work is true in the most extreme sense, and to supply 

 material to replace tissue destroyed in this work food is necessary. 

 Even ''father"' of the popular song who "lies around all day" 

 probably found it necessary to take some nourishm.ent. In addi- 

 tion to these unconscious or automatic exertions which accompany 

 the mere act of living most of us find it necessary to do various 

 and sundry acts known as work or labor. This work whether 

 it be the mental efifort necessary in the preparation of a paper for 

 the Farmers' Institute ; the vibration of the vocal cords of a candi- 

 date for election addressing an audience ; the tension of the mus- 

 cles of a road laborer as he rests on his pick or hoe handle ; m 

 short any motion or use of any part of the body is the result of 

 decomposition or breaking down of tissue. This tissue must be 

 renewed or the capacity for work ceases. This renewal is effected 

 by food. What then is food? How does material which is food 

 differ from that which is not? 



We have in nature what vv-e call forces or sources of energy 

 such as heat, light, electricity. These forces can be transformed one 

 into the other, for example the heat of burning coal becomes trans- 

 formed through the steam of the boiler into the motion of the 

 engine, then into the motion of the dynamo and finally in'.o the light 



