FOR MEADOW AND PASTURE LANDS. 155 



This ammonia, this infections odor, so valnable, so indispensa- 

 ble to the earth, is not h)st forever when it flies away into the 

 air. Bnt does not the shrewd farmer perceive that as much of 

 this as he allows to escape from his own lands, by neglect, 

 falls upon, and improves the fields of his neighbor as much, 

 and perhaps more, than his own ? Is it not evident that by 

 saving all that he can, and by receiving whatever the genial 

 rain brings with it, he gets a double benefit ? 



If the effect of plaster is such as we have described, no one 

 can fail to see how important are the functions it may be made 

 to perform. But it also adds a certain amount of lime and sul- 

 phur to the earth. It is composed of these substances for the 

 most part, and hence called by chemists, sulphate of lime. We 

 shall have occasion to speak of its use in connection with other 

 manures, when we speak of the compost heap. We now allude 

 to its use by itself, as a top dressing. 



On some soils it is not so satisfactory as on others. But our 

 pastures are many of them covered with the white honeysuck- 

 le. These might be called clover lands. On all clover lands, 

 whether reserved for pasture or mowing, plaster has a most 

 wonderful influence. No other manure produces such an enor- 

 mous increase of vegetable growth, in proportion to the quan- 

 tity applied. Most manures require to be used in quantities 

 far exceeding the bulk of the expected increase. Not so with 

 gypsum. A bushel, or two bushels to the acre, have been 

 known to double the crop, and to add more than twenty times 

 its own weight to it. Even greater results have followed. For 

 if we may believe one of the most distinguished French chem- 

 ists,* every pound of nitrogen which we add to the grass, in- 

 creases the produce one hundred and ten pounds, and this in- 

 creased produce of one hundred and ten pounds is effected by 

 the aid of a little more than four pounds of gyysum, or plas- 

 ter. Another accurate investigator,! found by actual experi- 

 ment that the ashes of an acre of red clover, contain no less 

 than three bushels of plaster of Paris. This important fact 

 proves that the earth already contains a large amount of this 



* Boussingault, Ann. de Ch. et de Pliys. t. 43, p. 243. 

 fDavy, Agricultural Chemistry. 



