8o6 
THE TROPICAL AGRICULTURIST. 
[June i, 1898 . 
sore to the country, owing to their neglected con- 
dition. The villager is threatened by the Govern- 
ment label “sales of land by villagers’’ and 
other consequences, and he is thus handicapped and 
so is the capitalist. We must repeat, in the interests 
of the country, that the policy adopted by Govern- 
ment is not only suicidal, but it is also a serious 
blow to the march of progress and civilization in the 
country. A tour round the North-Western Province 
and among the coconut estates there will amply 
repay the intending investor. He will note what 
land there is available for opening up, both from 
the Crown and natives, and what planted land there is 
to be had. A year ago, the value of laud all round 
was not the same as the price asked for now. This 
is not to be wondered at, for the Province is making 
wonderful progress, though slowly, since the rail- 
way line was opened. Since labour and capital 
have been brought in to once a feverish and dreaded 
Province, and with the increase of the chief industry, 
the trade is daily increasing, and price of land is 
looking up. When Givernment finally decides to 
throw up its inane policy of restricting the sales 
of land by villages to capitalists, and thus assist 
both the villager and capitalist, its Customs returns 
from shipments of copperah to Europe will alone 
be a principal revenue to the island — not to speak 
of nuts, oil, or “ dessicated.’’ — Local “ Times.’’ 
THE USE OF ARTIFICIAL MANURES. 
Is IT A Contradiction, OE What? — In the Journal 
of the Roijal IJorticidtural Society, vol. xxi.. Part I., 
August, 1897, p. 37, in a paper on “Artificial 
Manures,’’ by Mr. J. J. Willis, I find the following : - 
“How much more useful these manures (stable 
and farmyard manures) could be rendered by an 
admixture with suitable artificial fertilisers.” 
And on p. 42 ; “ Artificial manure.s, therefore, are not 
recommended to take the place of farmyard or stable 
manure, but to be used in conjuction with them.” 
On the other hand, in the Journal of the Royal 
Afjricultural Society of England, third series, vol. viii.. 
Part III., No 31, Sept. 30, 1897, now before me, I 
find the following in a paper on “ Recent Experiments 
on Denitrification.” On p. 477; “Notwithstanding 
the high position that artificial manures now take in 
the estimation of farmers in all parts of the world, 
it cannot be said that they have done anything to 
displace the use of farmyard manure, which must 
still be regarded as - our most general and important 
fertiliser. All the ^armyard manure produced in 
this country is still applied to the land, and arti- 
ficials find their legitimate place as sources of plant- 
food on areas that the available supply of home- 
made manure is insufficient to dress.” 
But observe what follows on p. 480 : “By a series 
of experiments and calculations, Maercker showed 
that from 12 to 47 per cent, of the nitrogen in nitrate 
of soda was dissipated through contract with the 
various forms of dung in the soil, and the loss was 
greatest when the largest quantity of dung w’as used.” 
And on p. 482 : “ It now becomes of interest to 
ascertain what becomes of the nitrogen that loses its 
nitric form in the presence of dung.” . . . • “ In 
every case it has been found that the nitrogen has 
been liberated in the elementary form.” 
P. 484 ; “ 'There is thus no escaping from the 
conclusion that nitrates, whether naturally present in 
manure, or the soil, or when added in so-called 
artificial manures, are rapidly destroyed by organisms 
(becteria) which are yery abundant in dung, and are 
also present, though to a much less extent in soil.” 
Further on p. 484 : “ It was found that the crop 
was least, and the loss of nitrogen greatest, in the 
mixture that contained most straw.” In other words, 
if you use nitrates in “conjunction” with dung, you 
may as well saye the money spent in artificial 
nitrates, and leave it in the saving’s-bank, for, if 
all that has been written be true, you will obtain 
no advantage from the use of the additional arti- 
ficial manure 1 
What is called “long manure,” with plenty of 
straw in it, seems to be the most wasteful, for the 
additional straw is prolific in denitrifying bacteria, 
which dissipate the nitrogen in its elementary form, 
and so render the nitrate valueless. 
However, on p. 485, this is stated: “Evidently, 
therefore the denitrifying power of the dung is lost 
to a large extent by contact with the soil for two or 
three months. ’ 
“ Wagner carried out a series of experiment?, which 
also go to show that the denitrifying becteria 
are much less energetic in old than in new dung.” 
In England it has been found that no appreciable 
increase of crop resulted when artificial manures, 
such as nitrates, were used with dung. And now 
German experiments appear to have solved this 
riddle. They seem to show that nitrogen is dis- 
sipated in its elementary form; that is, it is lost or 
wasted by contact with dung ; and fresh dung, when 
used in “conjunction” with nitrates, is far more 
wasteful than well-rotted dung, ‘ for the reason that 
the denitrifying organisms so abundant in the dung 
instantly attack to the nitrate of soda (or other nit- 
rate, aud also sulphate of ammonia, &c.) and dissipate 
the nitrogen in the elementary form.” 
I suppose we may infer that it would require 
the noduless of leguminosae to capture this elementary 
nitrogen again, and mikj it available for the growth 
of plants. The curious thing is, that purely phos- 
phatic and potassic manures also fail to produce 
satisfactory results when used with dung ; “ but 
Wagner’s experiments show that the negative results 
obtained, when mineral-manures are added to dung, 
are intimately associated with denitrification.” 
The conclusion to be drawn from all these experi- 
ments, if they are reliable, is first, that dung-heaps 
should be frequently turned, “so as to induce rapid 
fermentation, oxidation, and a high temperature ” 
before using them; and second not to use dung in 
“ conjunction ” with artificial manures, and especially 
with nitrates. 
There can be no doubt whatever that farmyard 
and stable manures are very valuable and important 
fertilisers. The whole agricultural history of man, 
all the world over, from the most primitive times, 
furnishes evidence of this. The safest plan would, 
however, seem to be to use home-made and well- 
rotted manures one year without artificial manures, 
and only artificial manures the next year. 
Artificial manures are trumpeted everywhere as 
the saviours of agriculturists and horticulturists, and 
no doubt if the soil wants these ingredients, and if 
the crops to be grown require them, they must be 
of advantage; the question, however, remains as to 
how and when these artificial manures should be used. 
Farm and stable manures have for ages given satis- 
factory results, under certain circumstances, that it 
would be a hopeless attempt to try and persuade 
practical growers not to use them ; the problem is, 
how and when to use them, when the soil needs 
some ingredients wnich these home made manures 
do not contiin. 
This subject is so important, from not only an 
individual but also a national point of view, that the 
more it is ventilated, the more is the likelihood that 
we shall get at the bottom of the conditions needed 
for scientific agriculture and horticulture. E. Bonavia, 
m.d, — Gardeners' Ghronicle. 
Palms oi'' Mattogrosso. — The Director of the 
Botanic Gardens at Rio Janeiro, Senr. J. Barbosa 
Rodrigues, has lately published a monograph of the 
Palms of this district, accompanied by twenty-seven 
lithographic illustrations. The sjiecies and varieties 
number nearly sixty. Among other things, we note 
a synopsis of the species of Cocos native to Brazil, 
and therein, under the section Glaziova, is included 
the Cocos Weddelliana, Wendland, which has been 
the subject of enquiry lately. This Palm is stated 
to be known at Rio by the vernacular name of Ika. 
—Gardeners' Chronicle, 
