88 
FLORIDA STATE HORTICULTURAL SOCIETY. 
THE ECONOMIC IMPORTANCE OF FIXED NITROGEN. 
BY L. HEIMBURGER, M.S., 
FIRST ASSISTANT STATE CHEMIST. 
Mr. President, Ladies and Gentlemen: 
Of the three natural elements so often 
deficient in our soils combined nitrogen 
is the one most easily exhausted, the most 
costly and the most rare. 
Every crop removes its aloquent por¬ 
tion of combined nitrogen from the soil, 
and if not returned by the grower leaves 
the soil proportionally poorer. Everv bat¬ 
tle results in the waste of hundreds even 
thousands of tons of nitrogen that could 
be used in supporting instead of destroy¬ 
ing human life. 
Again our sewers are delivering un¬ 
told millions of dollars of nitrogen an¬ 
nually into the sea. 
Every pound of coal or wood as or¬ 
dinarily burned, results in the return to 
the atmosphere of a definite amount of 
nitrogen. 
The problem is to replace this annual 
loss of combined nitrogen and as our 
two chief sources at present are neither 
inexhaustible, it becomes a serious mat¬ 
ter. These two chief sources arc our coal 
beds and nitrate deposits. Of the coal 
burned only a comparatively small 
amount of the nitrogen content is saved 
and our visible supply of Nitrate is be¬ 
ing rapidly exhausted. 
At the present increasing rate of ex¬ 
portation, now one and a half million 
tons annually, the Chili nitrate deposits 
cannot last more than another twenty 
years. 
Nitrogen is one of the least active 
chemically of all the elements, and for 
this reason, it is found in nature principal¬ 
ly in its free uncombined or elementary 
form. It is only by the most drastic of 
chemical or physical methods that elemen¬ 
tary nitrogen can be made to combine 
with other elements. The ultimate 
source of all our nitrogen combined and 
uncombined is the atmosphere where it is 
present in its elementary form to the ex¬ 
tent of about 79 per cent, by volume. The 
remaining 21 per cent, is principally oxy- 
gen. 
The greatest direct economic value of 
elementary nitrogen in the atmosphere 
is to act as a delutant to the oxygen. In¬ 
cidentally it is the source of all combined 
nitrogen. 
Elementary or uncombined nitrogen 
has no neutrant value to the higher or¬ 
ganisms and therefore is of no direct 
value to the plants and animals we are 
most interested in. 
In its combined forms nitrogen is one 
of the bases of life among higher organ¬ 
isms being a principal constitutent of pro¬ 
toplasm; the others being Carbon, Hy¬ 
drogen, Oxygen, Sulphur and Phospho¬ 
rus. 
If it were not for combined nitrogen, 
life as we now know it would be impos¬ 
sible. 
Here the question may be asked, how 
is the free or elementary nitrogen which 
is so inactive chemically, made to combine 
in nature with other elements so that 
higher life may be possible? 
