ARCH 2, 1903.] 
THE TROPICAL AGrvICULTURIST. 
THE NEW PHOSPHATE MANURE. 
{From Mr, John Hiighes.) 
Dundee, Jan. 20.— I am up here to explain at 
the annual meeting of tlie Dundee Farmers' Club 
the properties and advantages of t!ie New Manure 
Basic Superphosphates which has attracted a good 
deal of attention and has been specially successful 
in Scotland where the soli is generally deficient 
in lime and the period of active growth limited to 
a few months in the year. Already the manu- 
facture has mounted tip to over 1,500 tons daring 
tlie last year alone and during the coming year 
the demand U likely to be quite double the above 
figures. Some has already gone out to Ceylon in 
compound manures for tea, also 100 tons to 
Jamaica, 50 tons to Adelaide, 20 to Demarara and 
some to the Cape. 
(Editorial Remarks.) 
Less than a generation ago the farming ranks 
provided some of the most unresponsive audiences 
for the man of science, especially when the subject 
down for exposition was only feebly in touch with 
the aliair of rent paying. If Mr Hughes, who 
lectured so clearly and with such hearty accept- 
ance yesterday evening to the members of the 
Carse of (iowrie Fa,rmer!,' Club, had made his 
discovery of basic superphosphate in the eis-hties, 
instead of some two years ago, he would have run 
the risk of being for a time at least a voice crying 
in the agricultural wilderness. Without a doubt 
the world is making advances. The constant 
small raid of educational agencies and the ever- 
widening stream of knowledge founded upon 
experimental science must needs liberalise the 
world and give increasing clearness of outlook to 
all those who would as much as possible translate 
thought into action. \\ hen Liebig dissolved bones 
with vitriol in order to make the resulting com- 
pound useful for plant life he was probably classed 
by some as a visionary, but when he was rapidly 
followed by Sir John Bennet Lawes the world 
' caught on,' to use the popular phrase. The 
super-phosphate by whose means Sir John worked 
into a handsome fortune is now, however, in some 
small danger fron\ the 'basic super,' which is 
nothing more than the old ' super ' with enough 
of added lime to render it alkaline. Already the 
prospects for the new phosphatic compound are 
highly favourable. It is making bold headway in 
tiie early stages of ' life ' without undue puSiing 
and log-rolling aids. — Dundee Advertiser, Jan. 21, 
AUDUESS ON THE NEW PHOSPHATE. 
Mr Hughes, who was most cordially received, 
began his remarks by referring to the early ex- 
periments conducted by the late Sir John Bennet 
I Lawes in treating m'neral i)hosphatc of lime with 
acid in oider to make the resulting compound 
more or less available for pbiut food. The acid- 
treated phosphate, or superphosphate as it came 
to be named, came to bs most extensively used, 
especially for root-growing. Over two years ago 
Mr Hughes began to experiment with high class 
superphos|>hate by treating it with certain pro- 
portions of lime, his object being to produce a 
phosphate high in soluldlity and with an alkaline 
instead of an acid reaction. The result was the 
snbstanoe now known as basic superphosphate — 
a very li^ht, dry powdery substance, occupying 
fully 2.i times the bulk of ordinary basic slag. 
In chemical composition the new pliospbate 
contains 25 to '27 per cent phosphate of lime, 
which, though not soluble in water, is readily 
soluble in the acid juices of the plant roots, Mr 
Hughes explained that the new manure contained 
from 33 to 35 per cent of lime in combination 
v.'ith phosphoric and sulphuric acid. The great 
advantage of the basic superphosphate, Mr 
Hughes claimed, is that it is ten times more 
soluble th'in slag, the figures being 06 8 against 
C"6 per cent. Treating the basic super and the 
slag with a very weak solution of citric acid, Mr 
Hughes found than 94 per cent of the former had 
dissolved against fully 38 per cent of the latter. 
The soils most suitable tor the new manure were 
those naturally deficient in lime. It was specially 
useful on peaty and cold stiff soils, and had 
already proved of great advantage to soils subject 
to finwer-and toe, As for times of sowing, Nov- 
ember till February were suitable, but it could be 
drilled in along with the crop in spring, a fair 
dressing being 3 cwts. per acre. Mr Hughe.s 
claimed that the new phosphate was a great 
improvement upon slag in rapidity of action, 
while its alkaline nature gave it an advantage 
over superphosphate, especially where land was 
deficient in lime or given to souring. The lecture, 
which was of a most practical and interesting 
nature, was followed with great closeness, and at 
the end Mr Hughes was heartily applauded.- Ibid. 
A POT OF BASIL. 
AND MOSQUITO PREVENTIVES. 
Mr. A. E. Shipley's interesting article (p. 205) 
on Ocimum viride and its influence on mosqui- 
toes recalled some observations that I made upon 
the papaw tree (C'arica papaia) in China. My 
house, on the bank of the river at Whanipoa, near 
Canton, was singularly free from mosquitoes, 
though the other houses on the same island were 
more or less infested with them. A line of papaw- 
trees, stretched between my bouse anil the river, I 
frequently watched these trees, yet I never saw 
a single insect alight on them, though flies and 
other insects settled ii! numbers upon the bamboos 
and banana-plants not far away. In fact, the 
papaw-trees seemed to keep insects at a distance 
and to act as a rampart guarding the house from 
mosquitoes. The probability of this suggestion was 
considerably strengthened by the increase in the 
number of mosquitoes entering the house after a 
typhoon had blown down two papaw-trees and thus 
i-uade a gap in the rov\, and by the still further 
increase when a second typhoon felled another of 
the trees, I have questioned a number of persons 
living in the tropics, and one of them stated that 
be was familiar with the fact that papaw-trees 
repelled mosquitoes. 
That the papaw-tree possesses some curious pro- 
perty — in addition to the noto'ious proteolytic 
action of its juice — is suggested by the widespread 
practice of hanging meat in its shade to render 
the meat tender. The custom is frequently regarded 
as a senseless one, but its wide distribution causes 
one to ask : is it not possible that the papaw-tree 
should exhale a gaseous product which either repels 
meat-destroying insects or exerts an antiseptic 
action on putrefactive bacteri;', or, finally, is a 
volatile ferment? The peculiar relation in resanl 
to temperiituie displayed by the proteolytic 
ferment of the papaw juice renders the last possi- 
bilitj' less improbable than at first impression. 
—Naiui-e, Jan. '22. Percy Groom. 
