LIMING THE SOIL. 59 



Questions. 



1. When muriatic acid is poured upon a piece of limestone rock, 

 what chemical changes take place? 



2. Of what use is lime in the structure of bones? 



3. If a bone is placed in muriatic acid; what part remains? 



4. Burn a piece of fresh bone to destroy animal matter and what 

 is left? 



The "Minimum Quantity of Lime" or "Lime Limit." 



Of heavy soils is 3 tons of lime per plowed acre. 



Of light soils is 2 tons of lime per plowed acre. 



(Plowed acre means: A top layer 6 inches deep one acre in size.) 



Dr. F. Heinrich, Agronomist of the Halle Agricultural Ex- 

 periment Station, Halle, Germany, discovered the necessity of 

 the "Lime Limit" for different crops. 



He simply used a soil which tested to be free of lime and 

 showed a neutral reaction on Litmus paper, mixed this soil with 

 agricultural lime in pots in proportions of 5-100%, 1-10%, 

 2 - IO %, 3-io%, 5-io%, i%, and found that a soil must have at 

 least 3-10% of Carbonate of Lime under normal conditions, in 

 order to bring Alfalfa to full growth. 



The following table explains his experiments : 



Alfalfa. 



Clover. 



1 no lime no tons per acre 3.4 



2 5/100% y 2 ton per acre 3.9 



3 1/10% 1 ton per acre 4.2 



4 2/10% 2 tons per acre.. 16.8 



5 5/10% 5 tons per acre 17.6 



6 1% 10 tons per acre 18.2 



