AGRICULTURAL CHEMISTRY. 45 



will be explained in another part of this work, in con- 

 nection with the use of fertilizers, the composting of 

 manures, the husbanding of resources for the growth 

 of plants, and other topics of practical agriculture. 



A brief description has now been given of the 15 

 elements^ which, in, their various combinations, con- 

 stitute neaply the whole of all known matter. (Ta- 

 ble L, 1st column, 1-15.) 



A very imperfect (because too short) account has 

 been given also of 20 important compounds derived 

 from those 15 elements. (Table II., 2nd column, and 

 below 1-20.) 



Of the formation of salts^ by the combination of 

 acids with bases (see Table III.), something has been 

 said. 



A consideration of the nature of salts, and of their 

 use in agriculture, will be reserved for another place. 



