34 MASSACHUSETTS AGRICULTURE. 



after all, it is not probable that any very considerable addition 

 will ever be made by man to the producing surface out of which 

 the growths that support human life must come. How far 

 human industry, ingenuity and science may avail in reclaiming 

 the naturally sterile regions of the earth, it may not be easy or 

 safe to affirm. Utter sterility, such as that of the great sandy 

 plains of Asia and Africa, is probably incurable by any means 

 that will ever be in the power of man. If we could first 

 make the rain descend, where there is no roughness or variety 

 of surface, and no vegetation, to disturb the equilibrium of the 

 atmosphere, and none of the geographical conditions on which 

 showers depend, vegetation would doubtless gradually encroach 

 upon the arid waste. Or if we could first produce vegetation 

 where there is no rain to water the parched ground, then the 

 fertilizing showers would, no doubt, by an atmospheric law, in 

 due time descend. 



But since we can command neither of these, we may as well 

 regard those great deserts of tlie eastern continent as irretriev- 

 ably doomed to perpetual unproductiveness. The great belt of 

 barren sand which stretches across the northern part of Africa, 

 and the centre of Asia, comprises about 6,500,000 square miles. 

 Adding to this the aggregate of smaller tracts of land equally, 

 or almost equally sterile, we have a total of about one-seventh 

 of land surface of the globe which cannot be made to yield any 

 tribute to human life or human luxury. The proportion is 

 remarkable. As one-seventh of time is morally excepted from 

 the term of human labor, so one-seventh of the ground is natu- 

 rally excepted from tfie field of human industry, enjoying a 

 grand and solemn Sabbath stillness. 



A second aspect in wliich the productive power of the earth 

 may be considered, is with reference to improved modes of cul- 

 tivation. It is impossible to fix a limit to the extent to which 

 . science and labor may increase the products of the soil. We 

 see a vast difference in this respect between different countries 

 equally favored by nature. Thus, in the Austrian Empire, 

 there is more land under cultivation than in the British Isles, 

 and this land is not of inferior quality, yet the production is 

 one-third less ; and this difference is mainly owing to the 

 superior intelligence and more skilful cultivation of the 

 Britons. Great expectations were entertained by theorists a 



