250 MENTAL AND PHYSICAL EXERCISE. 



so necessary, that not only health, but even life itself 

 depends upon them. 



" Laughter," says Dr. Willich, "is sometimes the effect 

 of joy ; but it frequently arises from a sudden disappoint- 

 ment of the mind, when directed to an object, which, 

 instead of being serious, and important, terminates unex- 

 pectedly, in insignificance. Within the bounds of mode- 

 ration, laughter is a salutary emotion ; for, as a deep 

 inspiration of air takes place, which is succeeded by a 

 short, and frequently repeated expiration, the lungs are 

 filled with a great quantity of blood, and gradually emp- 

 tied, so that its circulation through the lungs is thus bene- 

 ficially promoted. It manifests a similar effect on the 

 organs of digestion. Pains in the stomach, colics, and 

 several other complaints that could not be relieved by 

 other means, have been frequently removed by this. In 

 many cases where it is purposely raised, laughter is of 

 excellent service, as a remedy which agitates and enli- 

 vens the whole frame. Experience also furnishes us 

 with many remarkable instances, where obstinate ulcers 

 of the lungs, or liver, which had resisted every effort of 

 medicine, were happily opened and cured by a fit of 

 laughter artificially excited." 



In cases, however, where the conscience is against the 

 practice of laughing, little good may be expected 

 from it. 



DIFFERENT KINDS OF MUSCULAR EXERCISE. 



There is a great difference in the amount of exercise 

 which men require, depending very much upon consti- 

 tution and habit. There is also a selection to be made 

 with respect to adaptation to the mind, since what would 

 prove exhilarating to some, might be mere drudgery to 

 others. Those who require muscular recreation, ought 

 therefore to select such as combine excitement with 

 convenience ; the same being adapted, with respect to 

 its greater or less violence, to the constitution and habits 

 of the individual. 



