376 PLAIN FACTS FOR OLD AND YOUNG 



organs of special sense; as the eye for sight, the ear 

 for hearing, the nose for the detection of odors, the 

 tongue for tasting, the skin and the mucous membrane 

 for the sense of touch. 



The Purifying Apparatus,— Waste matter accu- 

 mulates in the body so rapidly that it is necessary to 

 have abundant and efficient means to remove the same, 

 and prevent death by obstruction. This work is per- 

 formed by the lungs, liver, kidneys, skin, and mucous 

 membrane. 



Each organ and tissue possesses the power to repair 

 itself. Animal heat, which is also necessary to life, is 

 not produced by any special set of organs, but results 

 incidentally from the various other processes named. 



The Reproductive Apparatus.— As there is a 

 stomach for digestion, a brain for thinking, a ]3air of 

 lungs for breathing, etc., so there are special organs 

 for reproducing the species or producing new individ- 

 uals. Unlike all the other organs of the body, they are 

 intended for use only after full development of man- 

 hood has been attained; consequently, they are only 

 partially developed in childhood, becoming perfected 

 as the person becomes older, especially after about the 

 age of fourteen to eighteen, when puberty occurs. The 

 lungs, the stomach, the muscles, and other organs must 

 be used constantly from the earliest period of infancy, 

 and hence are developed sufficiently for efficient use at 

 birth. The fact that the sexual or reproductive organs 

 are only fully developed later on in life is sufficient 

 evidence that they are intended for use only when the 

 body has become fully matured and well developed. 



The Downhill Road.— In every large city, and in 

 small ones, too, even in little villages, we can scarcely 

 step upon the street without being pained at meeting 



