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clover, &c., is well known to Micliicran farraera. Some complain that il 

 has a tendency to retard the ripening of wheat, which makes it subject 

 to rust, <fec. This evil may be remedied by putting on the plaster early 

 in spring, and also by adding a little salt; this latter subatance promote* 

 the weight and ripening of all kinds of grain. 



The urate of the London manure company, is gypsum steeped in 

 urine, and it is esteemed a very valuable manure. The best time to ap- 

 ply gypsum is in the spring, when the land is not too wet, nor yet too 

 dry. Tlie following questions were addressed by M. Boussingault, to 

 eminent agriculturists living in different parts of France, in order to 

 determine the value of gypsum : 



Q. Ist. Does gypsum act favorably on artificial meadow? 



43 answers returned — 40 yes — 3 no. 



2d question — does it act favorably on artificial meadows, when th& 

 ground is extremely wet? 



10 answers — no unanimously. 



3d question — can it take the place of organic manures or of humus, 

 in the soil ; in other words,can a sterile soil with the addition of gypsum, 

 support artificial meadow ? 7 answers — all in the negative. 



4th question — does gypsum in a sensible manner increase the growth 

 of grain cropn? 



32 answers — 30 negative. 



The reader can compare the opinions of these agriculturists with his 

 own experience in the use of gypsum. 



The quantity of plaster usually applied to crops varies from one to 

 four hundred weight. 



Professor Johnston asserts in his lectures on Agricultural Chemistry, 

 that the addition of salt greatly increases the value of gypsum aa a 

 manure, and the great German Chemist, Liebig, is of the same opinion. 



Common Salt. 



Salt is certainly a very valuable manure, its uses in agriculture ap- 

 pears to be as follows: 



Ist. It supplies soda and chlorine. 



2d. It attracts moisture and resists frost. 



3d. It is soluble and attracts porous substances. 



4th. It promotes putrefaction when used sparingly. 



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