306 MASSACHUSETTS AGRICULTURE. 



A less amount than this will probably suffice, (as losses are 

 considerable,) unless the drainings of the barnyard are mingled 

 with the urine. Of course the contents should be agitated by 

 a proper wooden instrument thrust into the opening of the 

 cistern when the acid is added. 



I have dwelt somewhat at length upon the subject of the pres- 

 ervation of drainings and liquid manures, because chemistry 

 teaches me their superlative importance, and because I am con- 

 vinced that every farmer in Essex county can secure them if he 

 will. How absurd it is for you, gentlemen, to spend your 

 money for guano, when from the drainings of each one of 

 your oxen or cows there may be produced each year fully five 

 hundred weight of solid extract, which in fertilizing power is 

 fully equal to Peruvian guano. 



In addition to the large amount of ammonia contained in it, 

 there would be fully six per cent, of potash, one of the most 

 important fertilizers we possess. How much chemistry may 

 aid the farmer in the formation of compost ! It teaches him 

 that several objects are to be accomplished in the furnishing 

 and blending together the ingredients of the heap. It informs 

 him what is necessary to produce that series of complex 

 decompositions and recompositions which ultimate in the pro- 

 duction of the most eminent plant-fertilizers. No sensible, 

 enlightened farmer will fail to form from year to year his heap 

 of compost. When properly arranged, it is to him a mine of 

 wealth ; when formed in a hap-hazard, unskilful manner, it is 

 oftentimes a partial or a complete failure. The cold, sour 

 humus of swamp lands is sometimes brought from a distance 

 and thrown into heaps, and with the addition, perhaps, of a 

 portion of spoilt hay, or decayed leaves or fruits, is called 

 compost, and applied* to the soil. Of course it fails almost 

 entirely of beneflftial results. The formation of such compost 

 is like a mixture made by adding together water, snow and ice. 

 It is easy to see that no very extensive combination of different 

 ingredients is effected by such manipulations. Chemistry is 

 capable of pointing out a wide difference between the swampy 

 material to which I have alluded and common pond mud, as 

 respects its fertilizing effects. The one is rich in carbonic acid, 

 which can be of no essential importance to most lands, as they 



