FARM MANURES 585 



of water a considerable contrast to the 86 and 87 per 

 cent presented by the cattle and swine excrements. 

 Cattle and swine manures, being very wet, are rather 

 solid and compact. The air, therefore, is likely to be 

 excluded to a large degree and decomposition is relatively 

 slow. They are usually spoken of as cold, inert manures 

 as compared with the dry, open, rapidly heating excre- 

 ments obtained from the horse and the sheep. 



In every case except that of swine the liquid portion 

 of the various excrements is much the richer in nitrogen, 

 containing on the average more than twice as much when 

 compared on the percentage basis. The liquid is also 

 richer in potash than the solid, averaging for the four 

 classes of animals 1.36 per cent as compared to 0.34 per 

 cent contained in the solid manure. Most of the phos- 

 phoric acid, however, is contained in the solid excrement, 

 only traces being found in the urine except in the case 

 of the swine. It is therefore evident that the liquid 

 manure, pound for pound, is more valuable in so far as 

 the plant-food elements are concerned. The advantage 

 leans heavily toward the urine also in that the constit- 

 uents therein contained are immediately available; this 

 cannot be said of the solid manure. 



489. Actual plant-food in liquid and solid excrement. - 

 While the liquid manure carries more nutriments to an 

 equal weight than the solid, it yet remains to be seen 

 which actually carries more of the primary food elements. 

 In general, more solid manure is excreted than liquid, 

 tending to throw the advantage toward the former in so 

 far as total food elements are concerned. The following 

 table, adopted from Van Slyke, 1 bears on this point : 



Slyke, L. L. Fertilizers and Crops, p. 295. New 

 York. 1912. 



