WORK AND WASTE 



weight of the food and water which enter it, together with 

 that of the oxygen which it absorbs from the air. And 

 this is proved to be the case. 



Hence it follows that a man in health, and "neither 

 gaining nor losing flesh," is incessantly oxidating and 

 wasting away, and periodically making good the loss. 

 So that if, in his average condition, he could be confined 

 in the scale-pan of a delicate spring balance, like that 

 used for weighing letters, the scale-pan would descend at 

 every meal, and ascend in the intervals, oscillating to 

 equal distances on each side of the average position, 

 which would never be maintained for longer than a few 

 minutes. There is, therefore, no such thing as a sta- 

 tionary condition of the weight of the body, and what we 

 call such is simply a condition of variation within narrow 

 limits — a condition in which the gains and losses of the 

 numerous daily transactions of the economy balance one 

 another. 



Suppose this diurnally-balanced physiological state to 

 be reached, it can be maintained only so long as the quan- 

 tity of the mechanical work done, and of heat, or other 

 force evolved, remains absolutely unchanged. 



Let such a physiologically-balanced man lift a heavy 

 body from the ground, and the loss of weight which he 

 would have undergone without that exertion will be in- 

 creased by a definite amount, which cannot be made good 

 unless a proportionate amount of extra food be supplied 

 to him. Let the temperature of the surrounding air fall, 

 and the same result will occur, if his body remains as 

 warm as before. 



On the other hand, diminish his exertion and lower his 

 production of heat, and either he will gain weight, or 

 some of his food will remain unused. 



Thus, in a properly nourished man, a stream of food is 

 constantly entering the body in the shape of complex 

 compounds containing comparatively little oxygen ; as 

 constantly, the elements of the food (whether before or 



