TLIE CAUSATION OF DISEASE. 99 



such a sheltered E is necessarily fatal to man : one or 

 two generations may linger on under it, but soon extinc- 

 tion occurs. It is, I say, " a necessarily fatal E," an E 

 to which the human organism cannot adapt itself. Other 

 organisms can — beetles, rats, mice ; but the monarch of the 

 earth sickens and dies under it. Wherefore, casting our eyes 

 back through the long past, we learn a lesson from our 

 far-off ancestors. We find that man was " intended " to live 

 in the open. 



The same conclusion is forced upon us if we seek informa- 

 tion in another direction. Let us watch a healthy child ; study 

 his instincts. They are worthy of study, for, as we shall see 

 in another part,* instinct is, in the strictest sense, the voice of 

 " Nature." The child is living, let us suppose, in the country. 

 So soon as he can toddle, what does he do ? Stay in doors ? 

 No. He is soon roving about the country, for no healthy child 

 will keep in doors unless compelled. Wind and storm have 

 little fear for him — off he will go. What country-bred child 

 does not remember the agony of being kept in during a rainy 

 morning ! Soon, as he grows older, he begins to climb the trees, 

 like his simian ancestors. What healthy boy — nay, may I not 

 even say, girl? — living in the country, has not climbed every 

 available tree in the neighbourhood ? Dickens somewhere 

 speaks of the little sparrows in some old London "inn," flying 

 about from tree to tree, and " playing at being in the country." 

 How many of the London children make a more ghastly 

 imitation of Nature ! 



In the suburbs, however, the attempt may be more successful. 

 For example, a gentleman, living in the suburbs of London, 

 has a few well-grown trees at the end of his tiny garden. When 

 his eldest girl was five or six, she took to climbing these trees. 

 No one had shown her how, for, being the eldest of the family, 

 her brothers were too young. A short time ago I visited this 

 gentleman on a summer's afternoon, and, looking out of the 

 window, beheld the same maiden (now fourteen) sporting among 

 the branches of the trees. This habit of the girl has given 

 great trouble to a kindly old lady next door. She has 



* Vide Part II. 



