THE CONDITION OF OLD AGE 19 



potato and in the other a very large potato, both of 

 which have come at the same moment from the same 

 oven, and that you have just started out for a cold 

 winter drive. You all know, of course, that in a little 

 while the small potato, though it was as hot as the 

 large one at first, wi 1 ! have lost its heat, will no longer 

 serve to keep the hand warm, but the other hand, in 

 which the bulkier potato is held, in which the volume 

 of the heat we might so express it, perhaps is cor- 

 respondingly great, benefits by the retained heat a 

 long time. Essentially similar to this is the difference 

 between the child and the adult. The child loses 

 heat with comparatively great rapidity the old per- 

 son at a comparatively slow rate. Hence it is neces- 

 sary for the child to produce more warmth in order to 

 keep up the natural normal temperature of the body. 

 When, therefore, we find that in the old person the 

 respiration is diminished, and that the production of 

 carbon dioxide from the lungs is greatly lessened, we 

 are not immediately to jump at the conclusion that 

 the quality of physiological action has been debased 

 that we see here a sign of decrepitude. On the con- 

 trary, the change is the result of physiological adapta- 

 tion, of suiting the performance of the body to its 

 needs.- This is one of the great wonders, one of the 

 mysteries of life, of which we here have a sample, 

 the constant adaptation of the means to the end. 

 That which the body needs is done by the body. A 

 child needs more warmth, and its body produces 

 more ; the old person needs less warmth, and his 



