COTTON CULTURE. 109 



not returned to the soil. The composition of the ash of 

 cotton seed has been found to be as follows : sixty-two 

 per cent., or nearly two-thirds, is phosphate of lime; thir- 

 ty-two per cent., or nearly one-third, is phosphate of po- 

 tassa ; the balance is made up of a little sulphate of po- 

 tassa, a little silica, with slight traces of the carbonates of 

 lime, magnesia, and potassa. 



Thus it appears that, as a dressing or fertilizer for cot- 

 ton lands, no substance is superior to cotton seed, and 

 when this is used as fully as possible, that is, when all the 

 seed of a crop is returned to the soil as manure, except 

 what is necessary to germinate the crop of the following 

 year, the consumption of chemical constituents in the soil 

 is very slow, being at the rate of sixty pounds for twenty- 

 five acres, or a little over two pounds to the acre. Of the 

 three mineral ingredients abstracted by the cotton-wool, 

 two are easily replaced, the potash and the lime.. Com- 

 mon wood ashes, and plaster, or slaked lime, or bones 

 burned or crushed, will easily supply this demand. The 

 requirement for phosphoric acid is not so easily met. 

 The demand for it is moderate and the consumption slow, 

 being at the rate of only half a pound to the acre, but the 

 necessity for this element, in order to produce a healthy 

 plant, is imperative ; and in all soils that are not alluvial, 

 that is, where there is not a great abundance of fine vege- 

 table mould, the demand for phosphorus is probably the 

 reason why diseases of various sorts, such as the rust and 

 the rot, attack the plant. 



In addition to lime and ashes, some fertilizer containing 

 the phosphates must be used. Compost, or barn-yard 

 manure, and bone manure, will supply this element. 

 Weeds abounding in the alkalies furnish profitable vege- 

 table matter for making a good compost. Muck or peat, 

 which is decayed vegetable matter in mass, contains a 

 large amount of the phosphates andthe alkalies. 



To give a summary then, of the best manure for cotton 



