200 EXERCISE OF THE LUNGS. 



thus shown to be in strengthening the chest, its in- 

 fluence extends still farther. If we examine the 

 position of the lungs as represented in the figure on 

 page 169, we shall see, that, when fully inflated, 

 they must necessarily push downwards and flatten 

 the moveable arch of the diaphragm D D, by which 

 they are separated from the belly or abdomen. This 

 alteration, however, cannot take place without the 

 diaphragm in its turn pushing down the liver, 

 stomach, and bowels, which it accordingly does, 

 causing them to project forwards and outwards. 

 But no sooner are the lungs fully inflated than the 

 contained air is again thrown out. The lungs di- 

 minish in size : the diaphragm rises, and with it all 

 the contents of the abdomen return to their former 

 position. The whole digestive apparatus is thus 

 subjected to a continual pressure and change of 

 place, and the stimulus thence arising is, in truth, 

 essential to the healthy performance of the digestive 

 functions, and is one of the means arranged by the 

 Creator for the purpose. Consequently, if the lungs 

 be rarely called into active exercise, riot only do 

 they suffer, but an important condition of digestion 

 being withdrawn, the stomach and bowels also become 

 weakened, and indigestion and costiveness make 

 their appearance. I have already alluded to this 

 subject in the chapter on muscular exercise; but 

 the principle will now be better understood with the 

 aid of the figure. 



After this exposition, I need hardly say that the 

 loud and distinct speaking enforced in many public 

 schools is productive of much good to the young, 

 and that in this respect the occasional songs in 

 which all are required to join in the Infant Schools, 

 and other institutions, are much to be commended. 

 Let any one who doubts their efficacy as exercises 

 of the lungs, attend to what passes in his own body 

 on reading aloud a single paragraph, and he will 

 find, not only that deep inspirations and full expira- 



