The Story-Book of the Fields 



remain cheap. The lime kiln is about 

 eighteen feet in height and is lined with bricks 

 able to endure the fire. There is an opening 

 at the base through which the lime can be 

 withdrawn when it is sufficiently baked. In 

 order to fill the kiln a rough arch is built with 

 large pieces of chalk above the hearth on 

 which the fuel is to burn, and over this arch 

 smaller pieces are heaped up until the building 

 is full. The fuel is either wood, brushwood, 

 turf or coal. When the baking is completed 

 the work stops, and the lime is removed by 

 breaking down the arch that supports the 

 whole. The whole heap collapses and falls 

 to the opening at the base, where it is 

 extracted. 



Another method, which is the oldest and is 

 still used in many places, consists in arrang- 

 ing the fuel and the chalk in alternate layers 

 in the kiln. The whole rests on a layer of 

 wood, which is lighted first, and when the 

 fire has spread through the mass, the open- 

 ing at the top is covered with sods of grass 

 so that the baking may be slower and more 

 regular. 



Nothing can be more simple than the pro- 

 duction of lime. We will now consider the 

 effect on the chalk from the heat of the 



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