RIGHT USE OF LIME IN SOIL IMPROVEMENT 



40 parts of calcium and 16 parts oxygen by 

 weight. 



Carbon Dioxide is a compound whose 

 formula is CO2. 



Calcium Carbonate, known also as car- 

 bonate of lime, has a definite composition, 

 containing, when pure, 56 parts CaO and 

 44 parts CO2. It is known to the chemist as 

 CaCOs, and forms practically all of very 

 pure limestones. Impure limestones con- 

 tain some earthy materials that became 

 mixed with the lime carbonate when the 

 rock was being formed. 



Calcium Hydroxide is a compound made 

 by permitting calcium oxide to combine 

 with water, and is known as lime hydrate. 

 It contains 56 parts by weight CaO and 18 

 parts water, and has the formula Ca(OH)2. 



Magnesium is an element, and is found 

 in magnesium carbonate, a compound that 

 is effective in correcting soil acidity. 



Magnesian Limestone. Magnesium 

 carbonate is usually found in combination 

 with calcium carbonate, and when about 47 

 per cent of the total carbonates is mag- 

 nesium carbonate, the limestone is known as 

 dolomite. 



Ground Limestone is the stone pulver- 



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