STUDY OF SOILS. 463 



trees, particularly hickory, sugar-maple, elm, oak, and beech ; 

 and they often abound in grape vines. 



The pot and pearl ashes, made from a ten or twenty acre 

 clearing in Western New York, frequently sell for enough to 

 pay the whole cost of felling the timber, cutting and burning 

 it, and preparing the ground for a crop. I never saw any good 

 land that was not rich in potash, and how to extract it from 

 mountains, hills, and valleys, for agricultural purposes, is a 

 problem to which I have devoted some attention. It must be 

 done by water, and applied to land by irrigation. All the salts 

 of the ocean are well known fertilizers dissolved in water ; 

 and if it were practicable to irrigate a farm with sea-water 

 once a year, guano, which is derived from fish and the ocean, 

 would never be needed. 



Such irrigation would soon render the granitic soils of New 

 England not unlike those of the Onondaga Salt Group of West- 

 ern New York. At no very remote period sea-water will be 

 evaporated in tropical climates to obtain immense quantities 

 of compound salts required to impart fertility to islands and 

 continents. Oysters and other shell-fish and corals find an in- 

 exhaustible supply of lime in the water of the ocean. Wheth- 

 er you study its minerals, its vegetables, or its animals, it is 

 found to be a vast reservoir of manure. 



Farmers should take enlarged and comprehensive views of 

 their calling. The resources of nature are unlimited; and we 

 have only to learn ways, and provide means for the wise use 

 and successfid application of those elements of power and 

 wealth which everywhere surround us. Agricultural meteorol- 

 ogy teaches us that under a temperature of 73° to 75° Fahr. 

 solar heat will raise sixty-five thousand tons of water in a day 

 from the surface of a lake two miles square. The mechanical 

 power of this heat may be better appreciated, when I inform 

 you that ten steam-engines of 200 horse-power each could 

 barely raise that quantity of water between 300 and 400 feet 

 in 24 hours. Heat radiated from the sun is the true source of 

 all the water-power in the world ; as it is also the true source 

 of all the steam-power, whether generated by the combustion 

 of coal, wood, or alcohol in a spirit lamp. The mechanical 

 force developed in human muscles, and those of your horses 



