406 



Artificial Farmyard Manure. 



[Aug., 



manufacturing synthetic urea would create conditions favourable 

 to its extended use. As an alternative source of nit ogen, 

 cyanamide (nitrolim) and sulphate of ammonia have been rsed 

 with success. Whilst cyanamide already contains sufficient J'ree 

 lime to keep in check any acid compounds formed during fer- 

 mentation, sulphate of ammonia must be supplemented by the 

 addition of a base, and for this purpose finely-ground chalk, 

 ground limestone, or waste lime from causticising plant at soap 

 works may be used. For general purposes it will be found that 

 upwards of f cwt. of sulphate of ammonia and 1 cwt. of finely 

 divided carbonate of lime per ton of straw are sufficient to induce 

 fermentation. The main obstacles to large scale opera- 

 tions at the present time arise from the great tardiness with 

 which raw straw takes up the moisture necessary for fermenta- 

 tion. Where pits are available this difficulty may be overcome 

 by allowing the straw to remain immersed for 2 to 4 days, 

 after which the free liquid may be drained off. In the case of 

 heaps or stacks on open ground no advantage appears to be 

 obtained by continued wetting with large quantities of >.^'ater, 

 and we suggest, as a more effective method of securing the neces- 

 sary saturation of the straw, sprinkling the heap comparatively 

 lightly with water and allowing a couple of days to elapse before 

 a second sprinkling is given. During this time a slight fermen- 

 tation with increase in temperature sets in, rendering the straw 

 more capable of absorbing a second slight application of water 

 than would otherwise be the case. When examination has shown 

 that the interior of the heap has become uniformly moist, 

 the source of nitrogen may be applied in the form of solution, or 

 in the case of cyanamide and other products, this may be broad- 

 casted over the surface of the heap and watered in. The moist 

 convenient method of making the heap, wetting the straw, i.nd 

 supplying the necessary nitrogen for fermentation depends so 

 much on local conditions that much must be left to the initiative 

 of the farmer himself. 



General Characteristics of Artificial Farmyard Manure. — 



Artificial farmyard manure prepared from straw is a well disinte- 

 grated plastic material in which the tubular character of the straw 

 has been to a great extent destroyed. There is an almost com- 

 plete absence of smell, the little there is being slightly fusty or 

 mouldy in character. When prepared through the agency of a 

 compound in the presence of free lime, there is a tendency 

 towards the production of a blackish colour, while if prepared 

 from soluble alkalies such as ammonium carbonate, Jiquid 



