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EFFECT OF SALT ON THE STRAW. 



it may dissolve silica, phosphoric acid, organic substances, &c., 

 and carry them, or enable them more readily and abundantly 

 to enter, into the plant. 



If analysis shall satisfactorily prove, what many have taken 

 for granted, that bright, strong straw always contains a larger 

 quantity of silica than such as is soft and weak, then it may be 

 considered as in some measure established, that when common 

 salt is found to strengthen the straw, it does in reality dissolve 

 silica in the soil, or in the compost heaps to which it is added, 

 arid carry it into the plant. 



The above are nearly all the functions we are at present able 

 distinctly to assign to common salt in reference to healthy vege- 

 tation. Whether as a compound body chloride of sodium it 

 performs, in reference to the plant as distinguished from the soil, 

 any other important office than that of conveying both its con- 

 stituents into the sap without injury to the parts of the plant, 

 is a point in reference to which I am acquainted with no facts 

 that enable us as yet to form an opinion. 



