June I, 1892.] 
Supplement to the " Tropical Agricnlturist.'' 
953 
Wattagama came to grief by eating rice that 
hail been cooked over a fire ignited with croton 
sticks. lint tlie ten planters of Jlatnlo took no 
need of this warning, till at last people in 
England began to make eniiuiries regarding 
the laxative (piality of certain brands of tea sent 
from Ceylon, by th'e use of whicli several persons 
would seem to have taken ill. Shortly after 
this almo.st all the croton tTeo.s on ton estates 
disappeared. Plantei'.s who diil not go in for tea 
were more fortunate and allowed their croton 
trees to remain, and at the pre.sent day are making 
some profit, ns since of late there has been a 
demand for this i>roduct. The writer being one 
of these fortimates might be congratnlated for 
his wi.sdom, but if the 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 throe 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 min’bers when the tree is shaken ; 
and fowls have been seen to gorge themselves 
with the grub. W’hat 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 {»s- 
sess poultry ought to prevent them eating 
the croton oil seed, ns they do eat it wlien they can 
get at it, and then beeome stupefied, pirouette, and 
gyrate like n apinnhig top till they drop dead. 
This potencj' of the seed does not however appear 
to affect the ground-doves, very common birds 
in the island, which feud on it quite freely. No 
other animals are known to Mt either the Jeaves 
or the seed. Where domestic troubles arise among 
tho.se more intelligent animals, the Tamil coolies 
employed on e.states where croton trees still 
exist, and Kamasamy gives his wifo 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 month much inflamed 
by the irritating poison, and the throat quite sore, 
'riie-so effects necessitate the patient being kept on 
milky butter nnd sweets for several days, and thus 
the husband of the victim has to pay rather dearly 
for his indiscretion ! 
A 1 . 1 . PnODUCTS. 
nitiukvino pekments of the soil. 
This form.s the subject of an instructive article 
hv Mr. J. M. M. Munro, in the ifcyirf Agricultural 
Society's Jounuil. In 1877, the experiments of 
Schloesing and Muntz threw an entirely new light 
on the matter of nitrification, the existence of 
which was well known to Boussingault as early 
as IH.'itl, though the jirocess by which nitrifi- 
cation went on was not then understood. The 
experiments of 1877 were taken up on the sug- 
gestion of Pasteur in 1862, that the oxidation 
in this cn.se (like that in the conversion of wine 
into vinegar) might bo due to the action of a 
living ferment and not to simple action of the 
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 tlie 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 w-e 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." Tlioso who worked industriously and fol- 
lowed up the scent were IVarrington, Winogradsky, 
Dr. and Mrs. Frankland, and apparently Mr, 
Slunro himself. 
Warrington, summing up the results of his 
experiments, tells us 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 tlie nitrifying fer- 
ments have an antagonism to organic matter. 
Mr. Munro says that the importance of this 
discovery is very groat ; 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 36 parts of nitrogen 
in the form of ommonia hare to he 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 nece.ssarj- 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 couditions to result in 
their destruction. This destructive work, wo are 
told, is also brought about by microbes, and is 
a property common to a great number of different 
species. Some of those are copable 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 the aeration of the soil brought 
about by drainage and good tillage. 
