SECRETARY'S REPORT. 225 



with the greatest luxuriance, and its load of beautiful green 

 was the wonder of the neighborhood. Its effect on clover and 

 Timothy is even greater than on pastures. Many have supposed 

 that plaster would exhaust the soil. This would not seem to 

 be the case, for as it takes four hundred and thirty parts of 

 water to decompose one part of plaster, its decomposition is 

 slow, and consequently its influence is felt for several years. 

 How, then, can it have such immediate and beneficial effects ? 

 It retains the fertilizing gas Avliich is constantly rising from fer- 

 menting vegetable matter, and gives it up at a proper time for 

 the nourishment of the plant. It does not, like lime, cause 

 vegetable matters to decay, but rather when they decay, holds 

 their most important parts from escaping. 



The infectious odor which rises from decaying vegetable 

 matter, from the stable, from the manure heap, and impercep- 

 tibly from the whole surface of the earth, is one of the most 

 important elements for the growth of the plant. Plaster fixes 

 this, and the first shower washes it into the earth to feed the 

 roots of plants. The relative value of manure depends, in a 

 measure, upon the amount of this noxious odor, this ammonia 

 which it contains. This gas, commonly known as hartshorn, is 

 an exceedingly powerful stimulant. Nor will it appear unimpor- 

 tant, when we bear in mind that two and one-quarter pounds of 

 this ammonia, lost by fermentation, is equal to the loss of one 

 hundred and fifty pounds of grass or grain. Scientific men will 

 say tiiat this gas is taken up in the atmosphere by the rain, and 

 descends with the rain to fertilize the earth. This is true. 

 This ammonia, this infectious odor, so valuable, so indispensa- 

 ble to the earth, is not lost forever when it flies away into the 

 air. But 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 tliat 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 

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

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



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