164 
Economy of Nitrogen. 
[April, 
king-problem of practical chemistry, is a duty still unful- 
filled and a triumph still unearned. It may again be urged 
that processes which do not “pay” in our hands may yet 
prove successful in those of Nature, with whom time is no 
objeCt. If ammonia is but sparingly manufactured in the 
upper regions of the atmosphere, it may perhaps be evolved 
by the aid of non-nitrogenous organic matter in some of the 
phases of fermentation or of eremacausis. Or the vital 
power of vegetables may solve the difficulty : the growing 
plant may arrest atmospheric nitrogen, and employ it in the 
formation of albumenoids. Method after method, thus 
pointed out as possible, has been carefully scrutinised. In 
most cases the experimental reply has been decidedly nega- 
tive, in a few equivocal, in none distinctly affirmative. It 
is undoubted that the atmosphere superincumbent upon an 
acre of ground must supply combined nitrogen enough for 
all the vegetation naturally growing upon this acre, and 
must be able to keep up the supply from century to century. 
Were this not the case old Mother Earth would long ago 
have lost her green, flower-embroidered mantle. But to 
grow the crops needful for the support of our human popu- 
lation we are obliged to make, upon every single acre of 
arable land, demands a hundredfold greater than Nature 
ever makes upon an acre of forest, or prairie, or swamp, or 
moorland. 
As we have thus increased our requisitions, and as we 
have still in another point deviated from Nature’s plan by 
not restoring to the soil what we take from it, we meet the 
universally admitted faCt that without a supply of nitro- 
genous manures the fertility of our fields declines. What 
proof other than this one faCt is required to show that there 
is in the economy of the world no recuperative power equal 
to our present power of waste, and that we are thus ren- 
dering nitrogen unavailable more rapidly than it is being 
combined or made available ? Our stock of solidified nitro- 
gen, like our supply of solidified carbon, is decreasing, and 
must ultimately come to an end. The case of nitrogen is, 
of the two, by far the worse, because Nature is manu- 
facturing fuel for us far more rapidly than she is producing 
albumenoids. 
What then remains ? The world may not, perhaps, be 
upon the whole more populous than it has ever been before ; 
but thanks to some of the inventions upon which we so 
much pride ourselves, thanks to the industrial development 
which has characterised the last three centuries, and to 
which history records nothing similar, waste — destruction 
