150 BENEDICT— THE INFLUENCE OF [February 4, 



among the Kansas farmers to actually burn corn. Several years 

 ago, a large wheat steamer became stalled in lake Huron and in 

 working her way against the ice for several days, exhausted her 

 fuel supply. As a matter of fact, she was brought into Detroit 

 by burning the wheat in her bins under the boilers. One of the 

 most striking instances that I ever heard of was one that occurred 

 on a coastwise steamer bound from Boston to one of the Maine 

 ports. This steamer in the latter part of the year found herself 

 encountering a severe gale and shortly the coal supply was wholly 

 exhausted. Recourse was had to the demolition of the interior 

 woodwork of the vessel, stateroom partitions, mattresses, furniture, 

 but as a matter of fact, the steamer was brought into Portland 

 harbor by burning a large cargo of hams under her boilers. 



As we commonly eat our food materials, for the most part they 

 are too moist to burn, although when the different food materials 

 are deprived of a greater part of their moisture by drying, they 

 burn quite readily. In so burning, they are converted to carbon 

 dioxide and water and a definite amount of heat is liberated during 

 this combustion. 



Whenever organic material is burned and completely oxidized 

 to carbon dioxide and water, there is a definite amount of heat 

 liberated for each gram burned. Fats liberate very much more heat 

 than do equal weights of sugars or starches, and protein, the third 

 important element in our food, liberates about the same amount 

 of heat as do the carbohydrates. If, therefore, we determine as we 

 can with a special apparatus, the heating value or fuel value of dif- 

 ferent ingredients in our diet and then measure the total amount of 

 food ingested, measure the heat produced by man and make due 

 allowance for the heat in the feces and the solid matter of the urine, 

 it is possible for us to strike a complete balance of income and outgo 

 of energy and see whether our measurements are in error or not. 

 So, on the one hand, we have a heat balance obtained by determining 

 the intake and fuel and the output of unburned material in the ash 

 and the heat directly produced. On the other hand, we have from 

 the chemical analyses of the respired air and the excreta a means 

 of knowing just how much protein, how much fat, and how 

 much carbohydrates have been burned in the body during a cer- 



