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sods, or other combustible matter, are to be used ; 

 the flues, except on the weather side, are to be closed 

 on the outside openings, and not opened except as 

 the wind shifts about. After a short time these 

 lu'aps, if properly fed, with dry sods or heath, will 

 b(> strong- enough in heat to burn stiff and even wet 

 day, in small quantities at a time, and repeated fre- 

 quently. As the inside fills up with burned clay, the 

 outer walls must be raised and always kept at least 

 1.5 inches higher than the burning heap, in order to 

 ]>revent the wind from acting on the fire at top ; and 

 as tlie walls become consumed, the breaches must be 

 madfi up, or rather new walls must be built. Thus 

 tlie kiln may be enlarged to any size ; and after get- 

 ting into proper heat, it wiU burn the largest lumps 

 of stiff' under soil, and can only be extinguished by 

 the carelessness of the workmen attending it. Lime 

 may very economically be burned with it. 



Half the world was going mad about burning 

 barren clay sometime ago; but I fancy that the 

 value of it has been overrated. The most beneficial 

 clay ashes are obtained from sods, roots of plants, 

 bushes, and other vegetable substances ; the value of 

 mere brick dust, of powdered crockery, may, there- 

 fore, be overvalued. This will act mechanically, like 

 gravel or rabbit sand, on stiff land, by loosening it, 

 and preventing it from uniting again so closely : it 

 will thus enable the roots of plants to extend their 

 fibres in search of food; but as a fertilizer, when no 

 vegetable matter is in it, I doubt if the burned un- 

 dersoil, without vegetable nuittet' (which is the kind 

 recommended for burning in kilns on clay lands,) 

 has any enriching properties. 



