AMERICAN HOME GARDEN. 505 



always upon that which is most desirable and proper, but upon 

 what can be had in their season of need. If, therefore, the 

 rains have carried off the elements of this and the two preced- 

 ing divisions from the barn-yard, and they have been previous- 

 ly largely cropped out of the soil and sold off without return 

 to the land, no grand and heavy crop can be expected. 



Under the general terms saline or inorganic elements are 

 included, in very various proportions, Silica or Flint, Lime, 

 Magnesia, Alumina, Potash, Soda, metallic Oxides, Phospho- 

 ric and Sulphuric Acids, Chlorine, and a few other constitu- 

 ents ; and, though their aggregates, as shown in this division, 

 are small as compared with those of Nos. 5 and 6, yet they 

 are, more or less of them., essential to every crop, and can not 

 be taken by the plant from the atmosphere, whence much of 

 the material for the others may probably be derived. Hence 

 this division becomes of special importance, showing as it does 

 the total amount of the privation which land sustains by the 

 loss of these elements in a given crop. 



By far the greater portion of these aggregates, however, are 

 derived from about one half of the elements named above. Of 

 the 24 Ibs. of inorganic matter given in the table as obtained 

 from the product of an acre of wheat, about 8J Ibs. may be Sil- 

 ica, 2 Ibs. Lime, 2 Ibs. Magnesia, 4^ Ibs. Potash, and 5 Ibs. 

 Soda ; and of the 240 Ibs. yielded by the straw, about 189 Ibs. 

 may be reckoned as Silica, 16 Ibs. Lime, 2 Ibs. Magnesia, 1J 

 Ibs. Potash, and 2 Ibs. Soda, with some 10 Ibs. Phosphoric 

 Acid ; the small remaining balance in both being composed 

 of minute portions of the other elements. The large predom- 

 inance of silica and lime is a remarkable feature in this divi- 

 sion, and may illustrate the natural law by which supply and 

 demand are regulated in the vegetable and animal kingdoms. 

 Without the silica, neither corn, grain, nor grass would stand 

 upright to maturity ; it forms the outer coating and strength- 

 ener of the stem of these and certain other plants, and may, 

 without impropriety, be said to furnish to them the bones of 

 vegetable growth. The lime is equally essential to the forma- 

 tion and strength of animal bones, of which it constitutes so 

 large a part. Extraordinary means are sometimes used to 



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