382 
Waste . 
[July, 
We may therefore sum up by saying that combined nitro- 
gen is indispensable to animal and vegetable life ; that the 
world’s stock of such combined nitrogen is relatively small ; 
and that the processes for its increase or recovery are 
tedious, and not adtive. Surely we might, under these cir- 
cumstances, expedt that if Nature were a consistent econo- 
mist she would most carefully watch over her supply of 
combined ammonia, and guard against its decomposition. 
Such, however, is not the case. M. J. Reiset has recently 
shown that a part of the nitrogen contained in the albu- 
menoid matters of animals is set free during the transform- 
ations going on in the body, and escapes as gas. When the 
liquid and solid excretions of animals enter into putrefadtion 
a part, indeed, of the nitrogen present reappears as ammo- 
nia or as nitric acid. But another portion is liberated, and 
takes the form of free nitrogen. A striking instance of this 
waste is seen in the case of sewage. Knowing the rain-fall 
and the water-supply of a town, and the amount of its 
population, we can form an approximate calculation of the 
quantity of nitrogenous matter which such sewage ought to 
contain. But if we then submit a sample of such sewage 
to analysis we shall find the result falls greatly below the 
most moderate estimate. From 20 to 50 per cent of the 
combined nitrogen originally present in the excreta has es- 
caped in the free state, and has been wasted. In the 
“Journal of Science” for 1878 (p. 145) we discussed man’s 
sins and shortcomings as regards the economy of nitrogen. 
We see now that Nature is guilty of waste of the very same 
kind. 
It has lately been forced upon our attention that the per- 
manent and decided enrichment of a soil by manuring is, as 
regards the nitrogenous constituents, difficult, if not abso- 
lutely out of the question. If we mix with the earth 
guano, blood, fish, or other nitrogenous matter, a rapid 
series of changes takes place. Not only does a part of the 
combined nitrogen escape in the free state, but the rest, 
under the influence of ferments present in the soil is ren- 
dered soluble far more rapidly than it is required or can be 
utilised by the growing crops, and is washed down and 
carried away in the drainage-water, passing ultimately into 
the sea. We have, indeed, no reason to suspedt that it is 
in this process decomposed, but its immediate utilisation on 
the earth’s surface is suspended. An enlightened economy 
condemns in man not merely the adtual destruction of any 
useful matter, but its being locked up in an unavailable 
form, or, figuratively speaking, its withdrawal from circu- 
