THE ENVIRONMENT 53 



size of the sun taken in relation with its dis- 

 tance from the earth ; the size of the earth, 

 which enables it to retain its present atmos- 

 phere; the eccentricity of its orbit and the 

 inclination of the ecliptic; the relative 

 amounts of land and sea, and a host of other 

 factors. Together these probably make of 

 the earth, in comparison with other bodies, 

 an extremely favorable abode for the living 

 organism. Yet it cannot be denied that in 

 detailed chemical constitution the earth is 

 certainly more or less typical of all similar 

 bodies. Moreover the earth's crust and its 

 atmosphere, being formed in accordance with 



ing continents, as formerly observed, be completely changed 

 by such an addition to the land, and the whole of their fertile 

 regions be reduced to arid deserts ? Now, this distribution 

 of sea and of land, so wonderfully adapted as it appears to 

 be to the present state of things, depends of course in a great 

 measure upon the absolute quantity of water in the world. 

 While, on the other hand, the relative gravity of water, as com- 

 pared with that of the earth, keeps the ocean within its 

 destined limits, notwithstanding its incessant motion. Thus 

 Laplace has shown that the world would have been con- 

 stantly liable to have been deluged from the slightest causes, 

 had the mean density of the ocean exceeded that of the earth ! 

 Hence the adjustment of the quantity of water and of its 

 density, as compared with that of the earth, afford some of 

 the most marked and beautiful instances of design." — Prout, 

 The Bridgewater Treatises, Treatise VIII, "Chemistry, 

 Meteorology, and the Function of Digestion." London, 1834, 

 pp. 18G-187. 



I 



