January 14, 1005. 
Gardening World 
MOTTO FOR THE WEEK: 
“In all places, then, and in all seasons, flowers expand their light and soul like wings.”— Longfellow. 
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Views and Reviews. 
New Sources of Nitrate. 
Centuries ago, in the time of the poet 
Virgil, it was well known amongst the Roman 
farmers that it was advantageous to sow 
crops of Beans, Vetches, Tares, and Lupins, 
not only to get an immediate and satisfac¬ 
tory crop, but also to get a good crop of 
Wheat, Barley, or other kind of corn in the 
following year. We may say, however, that 
it was merely a question of observation of 
which they were able to profit, but they 
could give no scientific explanation, and 
could therefore follow out the investigation 
no further. It is only in comparatively re¬ 
cent times that any scientific explanation 
could be given of the above fact. 
Many experiments, however, have been 
made both in this country and on the Con¬ 
tinent to demonstrate that leguminous plants 
such as those above mentioned were able 
not only to collect their own nitrogen, but 
to benefit succeeding crops that usually have - 
a difficulty in finding the necessary supply of 
this element of plant food. Many were the 
explanations to account for the quantity of 
nitrogen which such plants contained, and 
left in the soil in their roots for the benefit 
of future crops. 
The next stage of the process was to dis¬ 
cover that plants having nodules upon their 
roots had some special means of collecting 
nitrogen which other plants were unable to 
do, and the conclusion was that the faculty 
was due to the presence of microbes or bac¬ 
teria in the nodules. Scientific men in more 
recent times have made experiments to 
demonstrate that these organisms in the root 
nodules are able to fix the free nitrogen so 
plentiful in our atmosphere. The agencies 
that can do this, apart from the microbes 
in the roots, are few, and probably only elec¬ 
tricity can effect it during thunderstorms 
and when directed by human agency under 
artificial conditions by introducing electri¬ 
city into experiments. 
Some years ago Dr. Fr. Nobbe, a cele¬ 
brated German chemist, carried out some in¬ 
vestigations by which he, was able to separate 
the bacteria in the roots of Clovers, Peas, 
and other crops, so that he could cultivate 
each organism separately in order to multi¬ 
ply the same, and then apply it to the crops 
artificially. He demonstrated that each 
different species of Pea plant had an or¬ 
ganism peculiar to itself or else the numer¬ 
ous closely allied organisms formed mere 
stages of one and the same species. Seeing 
that these organisms were so numerous, he 
made no attempt at giving them separate 
names, but collectively termed them “ nitra- 
gin.” 
We gave an account of some of his ex¬ 
periments, with the results, in The Garden¬ 
ing World for September 11th, 1897. About 
that time Dr. Nobbe’s discoveries were caus¬ 
ing some excitement, but as his investiga¬ 
tions were not continued sufficiently long to 
get at the details of the case the results 
finally proved disappointing, on account of 
many failures of the organisms to produce 
the results when the soil was inoculated with 
the same. 
Some of his preparations of nitragin were 
sent to the Gardens of the Royal Horticul¬ 
tural Society at Chiswick, but they proved 
a failure there, notwithstanding the success 
that attended the experiments in some other 
parts of this country. In Germany some 
excellent results were obtained, but the same 
causes that operated against continued suc¬ 
cess there were practically identical with 
those which were the ultimate cailse of 
failure in this country. About 80 per cent, 
of the cultures in this country proved a 
failure, and, as might have been expected, 
the nitragin disappeared from the market. 
(The word nitragin must not be confused 
by our readers with nitrogen, the element of 
plant food with which we are now concerned. 
Nitragin is the name applied to the microbes 
found in the nodules on the roots of the 
Pea family, as before stated.) 
After the removal of the organisms from 
the root nodules of plants, the bacteria were 
cultivated in solutions of the plants from 
which they were taken with the object of 
multiplying the organisms, and the failure 
of this experiment was due to the fact that 
too much nitrogenous matter was employed 
in the food supply to the organisms. 
Where the German doctor left off, the ex¬ 
periment was taken up by Dr. Geo rue T. 
Moore, of the Laboratory of Plant Physi¬ 
ology, U.S. Department of Agriculture. He 
soon discovered that the method employed 
by the German investigator was not suitable 
for maintaining the life of the bacteria. 
The latter were placed in decoctions of the 
host plant and grew luxuriantly, but Dr. 
Moore discovered that they became less and 
less active until they'completely lost the 
faculty of fixing the free nitrogen of the air. 
The organisms were, in fact, over-fed, and 
