OF THE FERTILITY OF SOILS. 149 



From every acre of this land, there were removed 

 in the space of one hundred years 1200 Ibs. of 

 alkalies in leaves, grain, and straw ; it became 

 unfruitful therefore, because it was deprived of 

 every particle of alkali, which had been reduced to 

 a soluble state, and because that which was rendered 

 soluble again in the space of one year, was not 

 sufficient to satisfy the demands of the plants. 

 Almost all the cultivated land in Europe is in this 

 condition ; fallow is the term applied to land left at 

 rest for further disintegration. It is the greatest 

 possible mistake to suppose that the temporary 

 diminution of fertility in a soil is owing to the loss 

 of humus ; it is the mere consequence of the 

 exhaustion of the alkalies. 



Let us consider the condition of the country 

 around Naples, which is famed for its fruitful corn- 

 land ; the farms and villages are situated from 1 8 

 to 24 miles distant from one another, and between 

 them there are no roads, and consequently no 

 transportation of manure. Now corn has been 

 cultivated on this land for thousands of years, 

 without any part of that which is annually removed 

 from the soil being artificially restored to it. How 

 can any influence be ascribed to humus under such 

 circumstances, when it is not even known whether 

 .humus was ever contained in the soil ? 



The method of culture in that district completely 

 explains the permanent fertility. It appears very 

 bad in the eyes of our agriculturists, but there it is 



