THE FOODS OF THE NEW EARTH 



same act would take place if the squash were 

 fed to a human being, — it would give off the 

 same heat that was measured on the ther- 

 mometer, and the body would have made use 

 of it. The steel tube, in technical words, was a 

 bomb calorimeter. In order to get a working 

 basis, the scientific men established what they 

 call a calorie. It is simply a unit of measure. 

 It is the amount of heat which would be 

 needed to increase the temperature of a pound 

 of water four degrees by the Fahrenheit ther- 

 mometer, or one and eight-tenths by the Cen- 

 tigrade. Or it may be measured in energy. 

 Thus the one calorie, if put into power, as in 

 a steam engine, would lift one ton a foot and 

 a half. Just as in coal there is what is called 

 latent heat, heat in reality which is in waiting 

 for the fire to come and turn it into actual 

 heat to warm us or cook our food, or run our 

 steamer across the ocean, so there is in foods 

 this latent heat waiting to be given out into 

 the body in the processes of digestion. The 

 calorimeter gives the opportunity of measur- 

 ing just how much latent heat there is in 

 foods, so that it becomes possible to tell of any 

 food just how valuable it is for body fueL 



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