168 fOOD AND WARMTH. 



CHAPTER XXXVI. 



THE CONNEXION BETWEEN EOOD AND WARMTH. 



The food wc eat partly gives us flesh, and partly 

 gives us warmth. It is within us as fuel for what 

 may be called a fire, which, when supplied with fresh 

 air, gives heat to every part of our bodies ; and 

 then, if this is so, we can understand that the greater 

 the exertion we make, or the work we do, the more 

 food will be necessary — just as when a train has to 

 go express pace it must have the fire of its engine 

 heaped up with more and more coal. If the fire gets 

 low, and the boiler cold, the train stops. So, when we 

 walk fast and work hard, unless our bodies arc 

 properly supplied with the food which replenishes 

 what is lost of both flesh and heat, we become ex- 

 hausted and waste away, and, if it went on, there 

 would at last be the coldness of death. 



Thus the Gree.nlander, in his very cold climate, 

 and with his very hard work, has need of a vast 

 amount of food, and will eat a quantity of flesh, fat, 

 and oil, which we should think enormous. On the 

 other hand, the natives of the hot climate of India 

 will be satisfied with very much less food — a simple 

 diet of rice, which we should think quite insufificient. 



Again, following out the same great law of life, 

 some animals, which are not able to obtain supplies 

 of their proper food in winter, creep into the 

 warmest spot they can find, and there, as it is termed, 



