146 Farmyard Manure, 



An imperial s;allon of this water was found to contain 84'88 

 grains of dry residue (dried at 220° F.), consisting of — 



Organic matter, and a little water of com- \ AQ.(\n. 



bination J 



Carbonate of lime 26*84: 



Sulphate of lime 5"73 



Phosjiliate of lime, with a little oxide of iron '65 



Carbonate of magnesia "50 



Chloride of sodium 1'25 



Potash -99 



Silica -92 



84-88 

 The amount of organic matter in this water is very great ; it 

 arises from the great excess of decomposing organic remains in 

 the soil, and imparted to the water a yellow colour and disagree- 

 able smell, not unlike the smell of water in which flax is steeped. 

 It will he further observed that even pure rain-water is capable 

 of rendering soluble a considerable quantity of all those mineral 

 constituents which are found in the ashes of our crops, and there- 

 fore are necessary to their growth. 



2. Filtration experiment made ivitli the draininrjs of a dung- 

 heaj} composed of fresh-mixed farmyard manure. — Having ascer- 

 tained in the previous filtration experiments that a soil containing 

 a good deal of clay and lime is capable of removing from com- 

 pound manuring substances all the more valuable fertilising con- 

 stituents, I was anxious to determine to what extent soils deficient 

 in both clay and lime possessed the property of retaining fer- 

 tilising substances from drainings of dung-heaps. The compo- 

 sition of the liquid used for this experiment is given above ; it is 

 the same liquid collected from a fresh dung-heap which in a 

 gallon contained 1357*74 grains of solid matter. 



The soil selected for experiment was a light, sandy, red- 

 coloured, very porous soil, containing, as will be seen by the 

 following analysis, only little clay and still less lime, but a good 

 deal of organic matter. It was submitted to a minute and careful 

 mechanical and chemical analysis, and furnished the results 

 embodied in the subjoined tables : — 



1. Mechanical Analysis. 



Moisture 3-45 



Organic matter and water of combination 13'94 



Coarse white quartz sand 47"00 



Fine red sand and a little clay deposited from water on \ -j^o.qo 



standing 5 minutes / 



Coarse clay deposited on standing 10 minutes .. .. 2'82 



Fine clay deposited from water on standing for 1 hour 6'30 



Finest clay kejjt in suspension in water after standing "I g.gy 



longer than 1 hour J 



100-00 



