MANURES. 73 



DRAININGS OF DUNG-HEAPS. 



Nobody can deny that farm-yard manure is seldom kept in the 

 most efficient manner. In many places in England, especially in 

 Devonshire, and in some parts of Gloucestershii-e, it is a common 

 practice to place manure-heaps by the roadside, often on sloping 

 ground, and to keep these loosely erected heaps for a considerable 

 length of time, before carting the dung on the field. On other 

 farms, the manure is allowed to remain loosely scattered about in 

 uncovered yards for months befoi-e it is removed. Heavy showers 

 of rain falling on manure kept in such a manner, by washing out 

 the soluble fertilizing constituents of dung, necessarily greatly 

 deteriorate its value. It is well known that the more or less dark 

 colored liquids, which flow from badly kept dung-heaps, in rainy 

 weather, possess high fertilizing properties. According to the 

 rain which falls at the time of collecting these drainings, according 

 to the character of the manure, and similar modifying circum- 

 stances, the composition of drainings from dung-heaps is necessa- 

 rily subject to variations. The general character of these liquids, 

 however, is the same in dilute and concentrated drainings. Sev- 

 eral samples of dung drainings were recently examined by me, and 

 from this analysis, it will be seen that they contain a variety of 

 fertiliziijg constituents, which it is most desirable to retain in 

 dung-heaps. 



The first liquid examined was collected from a dung-heap com- 

 posed of well-rotted horse dung, manure from fattening beasts, and 

 the dung from sheep pens. Both the horse dung and the dung from 

 fattening beasts were made in boxes. The liquid which ran from 

 this dung-heap was collected in rainy weather, and contained, no 

 doubt, in addition to the liquid portion of the dung, a good deal of 

 rain. 



The amount of free ammonia (ammonia expelled on boiling the 

 liquid) in these drainings was determined in the manner described 

 above ; and after the free ammonia was removed, quick lime was 

 added to the remainder of the concentrated liquid, for the purpose 

 of separating any ammonia present in the form of salts, which are 

 not decomposed simply by boiling. 



In this way the following results were obtained : One imperial 

 gallon of drainings contained 36.25 grains of free ammonia, and 

 3.11 grains of ammonia in the form of salts, not decomposed sim- 

 ply in boiling, but by continued boiling with quick lime. Evapo- 



