316 ' TALKS ON MANURES. 



acid. And so a farmer who raises a ton of timothy-hay per acre, 

 and sells it, sends off as much phosphoric acid in one year as such 

 a Cheshire dairyman as I have alluded to did in fourteen years. 



What the dairymen want, and what farmers generally want, is 

 nitrogen and phosphoric acid. Bone-dust furnishes both, and this 

 was the reason of its wonderful effects. 



It does not follow from this, that bone-dust is the cheapest and 

 best manure we can use. It is an old and popular manure, and 

 usually commands a good price. It sells for all it is worth. A 

 dozen years ago, I bought ten tons of bone-dust at $18 per ton. I 

 have offered $25 per ton since for a similar lot, but the manufac- 

 turers find a market in New York for all they can make. 



Bone-dust, besides nitrogen, contains about 23 per cent of 

 phosphoric acid. 



" That does not give me," said the Deacon, " any idea of its 

 value." 



" Let us put it in another shape, then," said I. " One ton of good 

 bone-dust contains about as much nitrogen as 8f tons of fresh 

 stable-manure, and as much phosphoric acid as 110 tons of fresh 

 stable-manure. But one ton of manure contains more potash than 

 5 tons of bone-dust. 



Bone-dust, like barnyard-manure, does not immediately yield 

 up its nitrogen and phosphoric acid to plants. The bone phosphate 

 of lime is insoluble in water, and but very slightly soluble in 

 water containing carbonic acid. The gelatine of the bones would 

 soon decompose in a moist, porous, warm soil, provided it was 

 not protected by the oil and by the. hard matter of the bones. 

 Steaming, by removing the oil, removes one of the hindrances to 

 decomposition. Reducing the bones as fine as possible is another 

 means of increasing their availability. 



Another good method of increasing the availability of bone-dust 

 is to mix it with barnyard-manure, and let both ferment together 

 in a heap. I am inclined to think this the best, simplest, and 

 most economical method of rendering bone-dust available. The 

 bone-dust causes the heap of manure to ferment more readily, and 

 the fermentation of the manure softens the bones. Both the ma- 

 nure and the bones are improved and rendered richer and more 

 available by the process. 



Another method of increasing the availability of bone-dust is by 

 mixing it with sulphuric acid. 



