39 



with that science, and we have already remarked the 

 application of geology to its uses. One of the great- 

 est improvements of farming in modern times, so 

 fruitful in improvements of every kind, is the free 

 use of mineral manures. Lime, in some form or other, 

 must enter into the composition of every soil, to ren- 

 der it fertile ; and where the chemist fails to detect 

 it in the land, he supplies it artificially. A know- 

 ledge of the analysis of soils is therefore necessary 

 to every good farmer. The use of mineral manures 

 is beginning to be well understood, and to be gene- 

 rally practised in our country; but there are two 

 things that appear either not to be fully comprehend- 

 ed, or not to be sufficiently brought into successful 

 operation; the one is to make a given quantity of 

 land yield, for a series of years, the maximum amount 

 of produce it is capable of by high culture and a ju- 

 dicious rotation of crops, and the other is the art of 

 irrigation. The great economy of making a small 

 portion of land yield as much as a large one, must 

 be too obvious to require explanation, and the man- 

 ner of effecting this important object is to be learned 

 by the application of scientific principles to husband- 

 ry. The wonderfully fertilizing effect of water has 

 been understood for ages, and the art of irrigation 

 has been practised from time immemorial. The 

 scriptures are filled with beautiful poetical allusions 

 to this art, which proves its antiquity, and it is still 

 practised in every part of Asia, throughout the south 

 of Europe, and in that portion of America settled by 

 the Spaniards. In those countries are seen extensive 

 works of irrigation, and where the depth of the bank 



