284 ITS BEARING ON MEDICAL PRACTICE. 



will outruu the leopard in a fair and open chase, because the work sup- 

 plied to its muscles by the vegetable food is capable of being given out 

 continuously for a long period of time; but in a sudden rush at a near 

 distance, the leopard will infallibly overtake the deer, because its flesh- 

 food stores up in the blood a reserve of force capable of being given out 

 instantaneously in the form of exceedingly rapid muscular action. 



In conformity with this principle, we find among ourselves an instinc- 

 tive preference given to farinaceous and fatty foods, or to nitrogenous 

 foods, according as our occupations require a steady, long-continued, slow 

 labor, or the exercise of sudden bursts of muscular labor continued for 

 short periods. Thus chamois-hunters setting out for several day's chase 

 provide themselves with bacon fat and sugar; the Lancashire laborers 

 use flour and fat, in the form of apple-dumplings; while the red Indian 

 ot' JSorth America almost transforms himself into a carnivore by the 

 exclusive use of flesh-food; he sleeps as long and can fast as long as the 

 puma and jaguar, and possesses stored up in his blood a reserve of force 

 which enables him, like a cat, to hold his muscles for hours in a rigid 

 posture, or to spring upon his prey, like a leopard leaping from a tree 

 upon the back of an antelope. 



If the i)recediug view of the muscular qualities developed by the two 

 kinds of food be correct, important inferences suggest themselves as to 

 the food that should be employed in relation to several kinds of work. 

 Of these inferences I shall select two examples : 



1. The nurses of one of our Dublin hospitals were formerly fed chiefly 

 upon flesh food and beer, a diet that seemed well suited to their work in 

 ordinary times, which was occasionally severe, but relieved by frequent 

 intervals of complete rest. Upon the occasion of an epidemic of cholera, 

 Avhen the hospital duties of the nurses became more constant, although 

 on the whole not more laborious, they voluntarily asked for bacon fat 

 and milk, as a change of diet from the flesh-meat and beer; this change 

 was effected on two days in each week with the best results as to the 

 health of the nurses, and as to their power of discharging the new kind 

 of labor imposed upon them. 



2. I have been informed, on competent authority, that the health of 

 the Cornish miners break down ultimately from failure of the action of 

 the heart and its consequences, and not from the affection of the lungs 

 called " miners' phthisis." The labor of the miner is peculiar, and his 

 food appears to me badly suited to meet its requirements. At the close 

 of a hard day's toil, the weary miner has to climb by vertical ladders 

 through a height of 100 to 200 fathoms before he can reach his cottage, 

 where he naturally looks for his food and sleep. This climbing of the 

 ladders is performed hastily, almost as a gymnastic feat, and throws a 

 heavy strain (amounting from one-eighth to one-quarter of the whole day's 

 work) upon the muscles of the tired miner, during the half hour or hour 

 that concludes his daily toil. A flesh-fed man (as a Red Indian) would 

 run up the ladders like a cat, using the stores of force already in reserve 



