MANURES 47 



dung must be piled in a heap in a convenient 

 place, starting with a layer of straw, and keeping 

 the sides of the heap upright, and covered with 

 a layer of earth to prevent nitrates volatilising 

 away as ammonia. By forming a heap in this 

 way there will be less loss of liquid, and what 

 does drain away may be caught in a shallow 

 trench surrounding the heap, with pits at 

 intervals, from which the liquid may be thrown 

 back on to the heap from time to time. 



Mixing. — In the application of artificial 

 manures care must be taken not to mix certain 

 manures together, e.g., lime or slag (which 

 contains lime) must not be mixed with, or sown 

 immediately after, dung, or volatilisation of 

 ammonia takes place. For the same reason 

 sulphate of ammonia must not be mixed with 

 slag, although it may safely be mixed with 

 super or bones. Nitrate of soda may be mixed 

 with slag, but not with acid manures such as 

 super. The phosphatic and potassic manures 

 can be mixed together without injury. Super 

 and slag are often mixed together, as both are 

 then more convenient to sow than by them- 

 selves. In any case, as mixtures of manures 

 are liable to become lumpy on standing, it is 



