March 1 , 1898 .] 
Supplement to the “ Tropical Agriculturist" 
653 
sary organisms are present in the soil. The 
conditions of the German experiments, con- 
tends Prof. Warrington, were clearly not such 
as to allow organic manures to be employed 
to advantage, and the results cannot be taken 
as indicating what may be expected to happen 
in the ordinary use of farmyard manure, for 
Prof. Wagner is him.self found to admit that 
his former experiments showed that under con- 
ditions which occur in practice n large p.upor- 
tion of the nitrogen of farmyard manure is 
recovered in the crop. 
We now hear of another series of pot experi- 
ments carried out at Pas-de-Calais by Pagnoul, 
the results of which showed that with moderate 
applications of dung (that is the solid excrement 
of manure, w’hich in the German experiments 
gave the very worst results) amounting to 20 tons 
per acre, the return obtained from nitrate of soda 
and sulphate of ammonia is not decreased ; 
indeed, in every instance the dung itself contri- 
buted to the increase ef crop. Lengthy 
reference is then made to the Rotham- 
stead experiments bearing on the question. 
Here, too, we are told that the returns 
yielded by nitrate of soda and ammonium salts 
applied with farmyard manure were “remarkably 
good.” In one particular experiment, however, 
we And that when rape cake and farmyard 
manure were used together in certain quantities, 
the return was not so good (in the case of a root 
crop) as where rape cake was used alone ; from 
which Prof. Warrington concludes that with 2,000 
lbs. rape and 14 tons manure (the quantities used) 
we apparently reach an amount of organic matter 
in excess of what can be economically used in an 
average season. 
The danger of denitrification reaching consider- 
able proportions will, it is pointed out, increase 
M the amount of fermentable organic matter 
In the soil increases, and will be much aggravated 
by a wet condition of the land. Those who 
employ dung in large quantities are, there- 
fore, more likely to suffer loss from denitrifi- 
cation. The mode in which farmyard manure 
is applied and the extent to which it is incorpor- 
ated with the soil must, says Prof. Warrington, 
have some influence upon its action. Where it is 
ploughed or dug in, and thus not intimately 
mixed with the whole soil (as in pot culture), it 
would be left in a succession of layers separated 
by unmanured soil. The denitrifying zone is, 
so to speak, limited, and does not include the 
whole of the soil penetrated by the roots. There 
is thus, says Prof. Warrington, much scope for 
careful enquiry as to the most profitable method 
of employing dung with other manures. 
The results furnished by the field experiments 
at Rothamstead, both with farmyard manure and 
with straw (the most|powerful denitrifying agents 
according to the German experimenters) do not subs 
stantiate the conclusions arrived at by them. The 
results obtained must be considered to be d ue to the 
special conditions of the experiments, and particu- 
larly to the large relative quantities of dung or 
straw which were employed. Prof. Warrington 
then indicates the lessons to be learnt from these 
famous experiments. One fact, he says, which we 
are taught is that ordinary farmyard manure is 
valueless as food for plqnts until It is nitrified, 
while the economy of large dressings becomes very 
questionable. Moderately dry soils are those 
most likely to yield a profitable return with farm- 
yard manure ; hence the importance of drainage. 
Prof. Warrington in conclusion points to the great 
variation in the manurial value of cattle manure, 
showing that its effect is clearly connected with 
the active and soluble nitrogenous matter it 
contains, while it has been shown that to the 
fermentable organic matters — of which the solid 
part of the manure is mainly composed — is to be 
traced the source of denitrification. The original 
voidings of animals, he points out, have a far 
greater manurial value than the final product of 
the manure heap. Lo.«s of nitrogen goes on in the 
whole progress from the stall to the field. One 
practical conclusion arrived at by the writer is the 
economy of keeping animals on the land when- 
ever practicable. 
It will be seen from the resumd which has been 
attempted, of Prof. Warrington’s exhaustive paper, 
that it in a great measure disposes of the difficult 
ties created by the German experimenters, while it 
also deduces many useful and practical conclusions 
on the subject of manuring which should prova 
of great value to local Agriculturists. C. D, 
OCCASIONAL NOTES. 
Mr. D. C. Jayawardene, an old boy of the School 
of Agriculture has, we are glad to learn, established 
himself as an agent for seeds. Mr. Jayawardene 
was a successful student at the School where he 
was particularly good in field work. After com- 
pleting his course of study he was for some time 
under Mr. J. H. Barber, and is at present on 
Abbotsford, Nanuoya. We understand that Mr. 
Jayawaideue has opened out a pretty extensive 
garden on his own account, and we hope to hear 
of him before long as a local Sutton or Carter. We 
can highly recommend the seeds of vegetables and 
flowering plants supplied by Mr. Jayawardene, 
who has also drawn up a Catalogue of the different 
varieties he keeps in stock. 
We have been asked to state what is the pro- 
portion of blood in the carcase of cattle, and the 
percentage of water in the blood. Steel in his 
Treatise on the Diseases of the Ox mentions that 
the blood' of the ox forms ,Vth of the weight of its 
body (that of the horse being estimated at 
Roughly blood may be said to yield on evaporation 
20 per cent solid residue, ami S J per cent water. 
The Sugar Industry in the West Indies has 
come to a critical condition, owing to low prices 
and the large importation of Indian Cooly labour. 
Demerara, which is not making its profits out of 
sugar, has just now half a million of coolies on hand. 
“ These coolies,” says t)ie Lzdian Ayriculturist for 
March last, “must by the contract made with the 
Indian Government receive constantly three 
shillings a day, or else Demerara must pay their 
passage and expenses back to India. Say that costs 
.TIO a head, Demerara cannot get rid of her coolies 
without paying a fine of five millions. She must 
therefore go on Sugar growing whether she likes 
or not. But, wherever sugar can be grown rhea 
can be grown also ; and cooly labour is quite 
