CHAPTER XXI 



Lime 



To make the mortar which is used in building 

 construction, masons make use of lime. 

 Stones, which look as if they were burnt, are 

 placed in a kind of basin surrounded by sand, 

 and water is poured over them. In a short 

 time the heap grows hot and burning, cracks 

 and falls into dust, while absorbing the water, 

 which disappears, being taken up by the 

 material, or evaporated by the heat. More 

 water is added till the whole is reduced to a 

 paste, which is mixed with sand, and the 

 result is mortar. 



Lime is derived from a very common 

 substance called chalk or, in scientific 

 phraseology, carbonate of lime. The process 

 is very simple. It consists in heating the 

 stone in kilns constructed in the open air, in 

 the vicinity of the places providing the fuel 

 and the chalk, in order to avoid the expense 

 of transport for a substance which must 



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