MANURES. 149 



dilute form (weakened by mixing it with a large 

 quantity of water) to the compost heap, where it will 

 change the ammonia to a sulphate as soon as formed, 

 and thus prevent its loss, as the sulphate of ammonia 

 is not volatile ; and, being soluble in water, is useful 

 to plants. Some idea of the value of this compound 

 may be formed from the fact that manufacturers of 

 manures pay a high price for sulphate of ammonia, 

 to insure the success of their fertilizers. "Notwith- 

 standing this, many farmers persist in throwing away 

 hundreds of pounds of amrnOmia every year, as a tax 

 for their ignorance (or negligence), while a small tax 

 in money not more valuable nor more necessary to 

 their success for the support of common schools, 

 and the better education of the young, is too often 

 unwillingly paid. 



If a tumbler full of sulphuric acid (costing a few 

 cents) be thrown into the tank of the compost heap 

 once a month, the benefit to the manure would be 

 very great. 



Care is necessary that too much sulphuric acid be 

 not used, as it would prevent the proper decomposi- 

 tion of the manure. 



In many instances it will be found profitable to 

 use sulphuric acid in the manufacture of super- 

 phosphate of lime (as directed under the head of 

 "phosphoric acid"), thus making it perform the 

 double purpose of preparing an available form of 

 phosphate, and of supplying sulphur and sulphuric 

 acid to the plant. 



