No one kind of lime can be named which will 

 Kind of lime invariably be the best to use. The buyer of course 

 to use. seeks maximum efficiency for the money and labor 



expended. The selection must therefore be in large 

 measure determined by relative prices as related to actual values. 

 The qualities of the more important materials between which choice 

 will usually lie will be briefly stated and figures indicating relative 

 content of actual lime (calcium oxide) will be given for such as are 

 fairly constant in composition. Information on these points will 

 make it apparent that choice should not be based upon ton price 

 alone. Composition and efficiency must be considered also. 



(i) Quick or burned lif/ie. This, if made by properly burning a 

 good limestone, should contain 95^0 or more of actual lime. One 

 hundred pounds (100) when slaked will take up about 30 to 35 

 pounds of water. It is best to slake such lime before spreading it. 

 This can be accomplished either by placing the lime in small heaps 

 in the field where it is to be used and covering with soil, when the 

 lime absorbs water either from the soil or by exposure to the 

 weather ; or more quickly and perfectly by sprinkling it with just 

 enough water to cause it to crumble into a dry powder. After water 

 is added the heap should stand a few days when it will be best to 

 shovel it over a screen to separate any lumps which are still 

 unslaked. Fresh slaked lime will prove more effective in correcting 

 most of the faults of soils needing liming than any other form of 

 lime. It will be especially desirable in soils rich in inert organic 

 matter, or in those containing a large proportion of clay. Limes 

 containing a large proportion of magnesia are less desirable as a 

 rule than the purer limes although the magnesia is not usually 

 without value in our soils. 



(2) Air slaked Hfiie. Air slaked lime is formed when burned 

 lime is exposed to the air, the more quickly in proportion as the air 

 is moist. Under such conditions the lime first absorbs water from 

 the air; later, if the exposure be long conttnued, it will also absorb 

 carbonic acid. From 130 to 170 pounds of fully air slaked lime are 

 required to furnish as much actual lime (calcium oxide) as is con- 

 tained in 100 pounds of fresh burned lime of good quality. For 

 most purposes the air slaked lime will probably answer almost as 

 well as water slaked lime, but it must be remembered that a larger 

 quantity is required to produce equal effect. 



