June I, 1892.] Supplement to the " Tvopical Agncultuvist: 
953 
Wattagama came to grief by eating rice that 
had been cooked over a fire ignited with croton 
sticks. But the tea planters of Matale took no 
need of this warning, till at last people in 
England began to make enquiries regarding 
the laxative quality of certain brands of tea sent 
from Ceylon, by the use of which several persons 
would seem to" have taken ill. Shortly after 
this almost all the croton trees on tea estates 
disappeared. Planters who did not go in for tea 
were more fortunate and allowed tkeir croton 
trees to remain, and at the present day are making 
some profit, as since of late there has been a 
demand for this product. The writer being one 
of these fortunates might be congratulated for 
his wisdom, but if tlie reader wishes for an 
instance where it was folly to be wise, he need 
only be told that not long ago he (the writer) had 
the misfortune to lose a good serviceable horse 
which died after three days' violent purging, 
supposed to have been caused by its having eaten 
some croton leaves from trees growing by the 
roadside. Sometimes this tree is infected with 
a kind of caterpillar which drops to the ground 
in large numbers when the tree is shaken ; 
and fowls have been seen to gorge themselves 
with the grub. What seems strange is that 
these birds were never known to have suffered 
any bad effects afterwards ; nor is it known 
that any people have been inconvenienced by 
eating the fowls in question. But those who pos- 
sess poultry ought to prevent them eating 
the croton oil seed, as they do eat it when they can 
get at it, and then become stupefied, pirouette, and 
gyrate like a spinning top till they drop dead. 
This potency of t)ie seed does not however appear 
to affect the ground-doves, very common birds 
in the island, which feed on it quite freely. No 
other animals are known to eat either the leaves 
or the seed. Where domestic troubles arise among 
those more intelligent animals, the Tamil coolies 
employed on estates where croton trees still 
exist, and Ramasamy gives his wife a beating, 
the latter not infrequently revenges herself by 
taking a mouthful of the poisonous seed and 
causes much consternation among her kith and 
kin, till the usual remedy of bathing the patient 
in cold water, to counteract the poison, is 
resorted to. Sometimes purging and vomitting 
continue for several hours, but ultimately stop 
after the bath, leaving the mouth much inflamed 
by the irritating poison, and the throat quite sore. 
These effects necessitate the patient being kept on 
milk, butter and sweets for several days, and thus 
the husband of the victim has to pay rather dearly 
for Ids indiscretion ! 
All Peoducts. 
^ . 
NITKIKVING FERMENTS OF THE SOIL. 
This forms the subject of an instructive article 
by Mr. J. M. M. Miinro, in the Royal Ai/rwu,ltuml 
Sociefi/'x Jounidl. In 1S77, the exporiuKuits of 
Schloesing and Miintz threw an entirely new light 
on tlie matter of nitrilication, the existence of 
whicli was well known to Boussingault as early 
as IHot), though the i)ropess by which nitritl- 
catiiiu wrnldu was not then uihUtsIooiI, Tlii^ 
experiments of 1877 were taken up on the sug- 
gestion of Pasteur in 1862, that the oxidation 
in this case (like that in the conversion of wine 
into vinegar) might be due to the action of a 
living ferment and not to simple action of tlie 
air. " Fifteen years after this suggestion " says 
Mr. Munro, " the first experiments confirming it 
were published, and not until the present year, 
that is after the lapse of nearly fifteen years more, 
has the prediction been fully and completely 
verified by the isolation and separate examination 
of, at any rate, two of the species of organisms 
concerned in the process." So slow, in certain 
cases, is the onward progress of what we are 
accustomed to regard as the rapid advancing 
strides of science. A considerable portion of 
the paper is taken up with the history of what 
Mr. Munro terms " the hunt after these organ- 
isms,'' Tliose who worked industriously and fol- 
lowed up the scent were Warrington, Winogradsky, 
Dr. and Mrs. Frankland, and apparently Mr, 
Munro himself. 
Warrington, summing up the results of his 
experiments, tells lis that all samples of soil 
taken down to 2 feet in depth provoked 
nitrification, but that over this depth failures 
to nitrify increase in number, and at a 
depth of 6 feet and over, the soil has lost this 
power. From this and other experiments it 
would appear to be certain that the first few 
inches of surface soil contain the ferments in 
vastly greater proportions than the subsoil. 
From the soil these ferments get into water, 
and the power which rivers and wells have of 
ultimately converting the ammonia of sewage 
into nitrate of lime (or other base) depends 
on their presence. 
One after another discoveries were made, 
the last and one of the most important being 
that of Winogradsky, that the nitrifying fer- 
ments have an antagonism to organic matter. 
Mr. Munro says that the importance of this 
discovery is very great ; it reveals an entirely 
new property of living things, that of building 
up from the carbon of mineral carbonates and 
the nitrogen of ammonia,the complicated albumin- 
oid and other organic constituents of living 
cells. It appears that about 35 parts of nitrogen 
in the form of ammonia have to be oxidised 
to a nitrate for one part of carbon taken in 
as food by the ferment : and it is the heat 
evolved by this large oxidation that furnishes 
the force necessary to effect the decomposition 
of the carbonate. 
Mr. Munro concludes his paper with the fol- 
lowing important reflection : — The practical point 
should not be lost sight of, that nitrates are 
destroyed much more easily and much faster than 
they can be formed. A free supply of air above 
all things favours their preservation, whilst the 
presence of organic matter in the absence of 
air is certain under natural conditions to result in 
tlieir destruction. This destructive work, we are 
told, is also brought about by microbes, and is 
a property common to a great number of different 
species. Some of these are capable of destroying 
in a few days as much nitrate as is formed 
in months or years. Fortunately, the activity 
of these baneful species can always be kept 
in abeyance by tlie aeration of the soil brought 
about l)y drainage uiul L;iiod tillage, 
