160 COCONUT PLANTER'S MANUAL. 



Other Sources of Lime. 

 Liming can, to a certain extent, be obviated by the use of manures con. 

 taining lime. 



Amongst the manures containing lime the most important is undoubted'y 



Basic Slag. 



This is a byproduct of steel manufacture by the Thomas and Gil- 

 christ process. In Ceylon the value of basic slag has been recognised long 

 ago, and this manure constitutes a favourite and cheap source of phosphoric 

 acid. This latter ingredient is required in large quantities for the formation 

 of the stem, branches and leaves of the tea plant; but, besides this, every ton 

 of basic slag contains approximately half its weight in lime. 



The following is a complete analysis of this fertilizer : — 



•Phosphoric Acid ... ... 2T24 per cent 



Lime ... ... ... 47'40 



Magnesia ... ... ... 3 60 ,, 



Oxide of Iron ... ... 10-40 



Manganese, Alumina. Sulphuric Acid, &c, 8"56 ,, 



Silica ... ... ... 6-00 



Loss on Ignition ... ... 2"80 „ 



100-00 



Citric Soluble Phosphoric Acid ... 15*87 per cent 



Finen ss ... ... .. 90*25 ,, 



•Equal to Tribasic Phosphate of Lime 46"36 ,, 



The article is usually sold on the basis of — 



"JO per cent Phosphoric Acid and 85 per cent fineness 

 17 ,, ,, ,, 80 ., „ 



The Value of Basic Slag. 



Basic Slag is undoubtedly well suited for Ceylon soils. These soils 

 contain the phosphoric acid in combination with various elements, princi 

 pally as phosphates of calcium, aluminium, iron, manganese, anil these 

 p hosphates are generaily tribasic, insoluble phosphates, incapable of being 

 taken up by the plant, unless being previouly rendered available by 

 chemical or microbical acinn. 



Rate of Application. — The rate of application is from 2 to 4 cwts. per 

 acre per annum. Loss of phosphoric acid through draining water is practi- 

 cally nil. 



[For these notes we are indebted to A. Baur -"Ceylon Manure Works.]"' 



