224 
On the Tlieoreticdl and Practical Value of 
it is admitted on all hands, are more energetic, and manifested 
by a more rapid action on vegetation than the same amount of 
nitrogen applied to the land in the shape of nitrogenous organic 
matters. In other words, nitrogen in the shape of ammonia- 
salts has a greater money-value than nitrogen in combination 
with organic matter. A higher price, for instance, is paid for 
the nitrogen in sulphate of ammonia than for the nitrogen in 
blood or for the nitrogen in shoddy. Too high a value for 
practical purposes, therefore, is put upon the manure-constituents 
of purchased foods if the calculation is made on the supposition 
that the whole of the nitrogen recovered in the manure from their 
consumption exists as ready-formed ammonia, for which an 
allowance at the rate of 8«?. per lb. is made. 
In the second place, I would notice that 8rf. per lb. is the market 
price at which ammonia is sold at present in concentrated 
portable manures, but that its money-value is much less when 
offered for sale in bulky fertilisers, in which a comparatively 
small amount of ammonia, say 2 per cent., has to be taken 
with a large proportion of water and bulky materials of no great 
fertilising value. The manurial residue of 1 ton of linseed- 
cake given to feeding beasts with straw and roots would be 
distributed through several tons of farmyard-manure. After 
purchasing such voluminous manuring matters, expense must 
be incuried for carriage and for their distribution upon the 
land. All this is saved to the farmer who buys the ammonia 
he wishes to apply to his crops in the shape of concentrated 
portable manure, which admits of ready application to the land, 
and can be placed upon it where it is most wanted, that is, in 
more direct contact with a starting crop than is the case with 
farmyard or bulky compost manures, which have to be ploughed 
in and mixed with a large portion of the soil. The practical ad- 
vantages obtained by the use of concentrated or portable manures, 
in enabling the farmer to incorporate them with only a small 
portion of the soil in more direct contact with the starting 
crop, receive a practical acknowledgment in the higher com- 
parative price which practical men find it answer their purpose 
to pay for ammonia in concentrated ammoniacal manures than 
they have to give for the same amount of ammonia in bulky 
manures. 
A reference to the composition of ordinary farmyard-manure, 
and the price at which it is usually sold, I trust will put this 
argument in a clear light. 
According to analyses made by me many years ago, the com- 
position of fresh and rotten farmyard-manure, being the mixed 
manure of horses, cows, and pigs, is the following : — 
