THE CHEMISTRY OK THE SOIL. l J"> 



Utilising Waste Bones on the Farm.- 



The following are amongst the best methods of utilising waste bones on 

 the farm, and converting them into manure when it is not feasible to grind 

 them : — 



1. Fermented Bones. — Bones may be decomposed and rendered more active 

 by mixing them with about one-fourth of their weight of loam, and keeping 

 the heap moist \\ ith stable-liquor or urine. The heap should be protected from 

 rain. By this process also there is a loss of nitrogen, but the phosphate is 

 rendered more readily available and proportionately increased. This is a 

 method that deserves to be made use of where bones are plentiful, and there 

 is no means of reducing them to powder. Thirty to forty bushels per acre is 

 the proportion recommended for grass lands. 



2. Another method of fermenting bones, which I have taken from the late 

 Mr. J. L. Thompson's notes in the Agricultural Gazette, is the following : — 

 Bones may be softened by mixing in heaps with quicklime and loam. A 

 layer 6 inches deep of bones, then a layer 3 inches deep of lime, and then a 

 layer about i inches deep of loam, and so on, repeating until the heap is 

 made of convenient height, when it is to be covered up with a thick layer of 

 earth. Holes are then bored into the heap from the top, and water 

 poured in to slake the lime. The mass will become hot, and remain so for 

 two or three months, after which the bones will be found very friable, and 

 the whole heap may be mixed together, and is ready for applying to the 

 ground. 



3. By conversion into superphosphate (see pages 96 and 97). 



Other Sources of Phosphoric Acid. 



Mineral phosphates are little used in the raw state as a manure ; but as 

 they form the basis of the bulk of the superphosphates and mixed manures 

 on the market, a short account of them will not be out of place here. 



The mineral known as apatite is a crystalline form of phosphate of lime, 

 and phosphorite a non-crystalline form. These occur as rock-masses or in 

 nodules embedded in rocks of sedimentary origin in many parts of the world, 

 notably Canada, South Carolina, Florida, England, Spain, and Norway. The 

 Canadian phosphate is a crystalline rock, the English coprolites are for the 

 most part spherical nodules found in the green-sand and chalk. 



Bock phosphates are found in considerable quantities in the islands in the 

 Pacific, whence they are imported to the mainland and used in the 

 manufacture of superphosphates. 



Ground phosphate is the name usually given to the above compounds when 

 finely ground. They are not much used in this condition, but if so employed 

 it is essential that they should be as finely ground as possible. They ate 

 non-nitrogenous. 



Guano, in its original signification, is the name applied to the dried dung 

 of fish-eating sea-birds, and is obtained principally from the rocky islands in 

 the Pacific and Atlantic Oceans. Guanos are either nitrogenous or contain 

 little or no nitrogen, the amount of this ingredient decreasing with the age 

 of the deposit. Guano was at one time very extensively used as a manure, 

 but it is being largely superseded by cheaper and more concentrated forms of 

 phosphoric acid and nitrogen. Nevertheless, it should not be overlooked, in 

 view of the quantity of it existing in the islands of the Pacific Ocean on" our 

 own coasts. 



