ACfTION OF SALT. 75 



properties. Common salt may be detected in 

 nearly all soils, and its elements are found in the 

 ash of almost all plants. 



The action of Salt in small quantity in soils, 

 generally, is to assist in decomposing the vegeta- 

 ble and animal matter present. In large quan- 

 tity it is very injurious, in fact, making the land 

 completely sterile. Hence the practice in an- 

 cient times of sowing large ^quantities of salt 

 upon the land surrounding conquered cities, thus 

 indicating the will of the conquerer, that the 

 land should be desolate and the conquered city 

 no longer habitable. 



Some plants and trees are injured by salt 

 much more readily than others. When applied 

 in excess to some fruit trees, as the apple, plum, 

 cherry and apricot, the leaves wither and die 

 within a short time; the willow, poplar and 

 beech are affected in the same way. On the 

 other hand, some species of oak, the mulberry, 

 the pear, and the peach, and some other trees 

 with deep roots, do not suffer from its applicar 

 tion ; neither do asparagus, onions, celery, etc. : 

 indeed, the growth of these plants is improved 

 by its use. 



Salt acts as an exterminator of some kinds of 

 insects in the soil. It has likewise been found 

 effective in destroying the wire-worm, and in 

 preventing mildew and rust. The danger of its 



