THE INFLUENCE OF EXERCISE UPON HEALTH. 327 



fortunate brothers, but must be a sober woman after she has entered 

 her teens. It seems as if the battle of modern life (at least of modern 

 city life) was a battle of the nerves. " From nursery to school, from 

 school to college, or to work, the strain of brain goes on, and strain 

 of nerve scholarships, examinations, speculations, promotions, excite- 

 ments, stimulations, long hours of work, late hours of rest, jaded 

 frames, weary brains, jarring nerves all intensified by the exigencies 

 of our school and city life." * The worst of the mischief is, that 

 this strain falls most of all upon those from nature and circumstance 

 least able to bear it upon our women. Public opinion frowns upon 

 their exercising like men. Yet, with a nervous system more sensitive 

 than man's, they need the very exercises (out-of-doors) which, by 

 a mistaken public sentiment, they are often forbidden to take. The 

 healthy house-work is often deputed to a servant either because too 

 hard for our American girls, or too much beneath them. 



Of the five agents of health exercise, food, air, sleep, and bath- 

 ing exercise, to a certain extent, regulates the demand for the other 

 agents. The muscles, when fully developed, constitute about a half 

 of the full-grown body. The muscular contractions act upon the 

 blood. The blood is the life-stream, carrying the atoms of nourish- 

 ment to every part of the body, and receiving the waste particles 

 which have already done their work. This process of depositing build- 

 ing substance and receiving waste matter goes on according to a law. 

 This law, called, from its discoverer, the law of Treviranus, is " Each 

 organ is, to every other, as an excreting organ. In other words, to 

 insure perfect health, every tissue, bone, nerve, tendon, or muscle, 

 should take from the blood certain materials and return to it certain 

 others. To do this, every organ must or ought to have its period of 

 activity and rest, so as to keep the vital fluid in a proper state to nour- 

 ish every other part." f So that, if we give to the muscles their share 

 of labor, as indicated by the ratio which they bear to the whole body, 

 according to this law, we ought to give a large proportion of our wak- 

 ing hours to their use. But there are certain involuntary muscles 

 doing their work all the time, night and day. In our usual vocations, 

 too, how T ever confining they may be, we are obliged to take a certain 

 amount of muscular exercise. Consequently, in the really necessary 

 work of any ordinarily busy person, the muscles do have a fair share 

 of exercise. Still, there are a number of muscles which are used almost 

 exclusively, so that other muscles, with their connecting tendons, bones, 

 and nerves, fail, from sheer neglect, to contribute to the health of the 

 whole body. How many women exercise fully the large muscles of 

 the back and loins, or the muscles of the abdomen ? Women who 

 wash, or those who work in field or garden. Yet these important 

 muscles, when used, contribute much not only to the health of the 

 body in general, but also to the vigor of the organs lying underneath 



* M Physical Training," McLaren. f " Wear and Tear," S. Weir Mitchell. 



