July i, 1889.] 
THF TROPICAL AGRICULTURIST. 
63 
an oblong pod wbich contains from two to five ovate 
compressed seeds. Modern botanists generally refer 
the plant to Glycine: which see. — B. S. 
(From " Simmond's Tropical Agriculture" .) 
That well-known sauce, Soy, is made in some parts 
of the East, from a species of the; Dolichos bean 
(Sqja hispida), which grows ill ^hina and Japan. In 
Java it is procured from the Phaseolus rachatus. The 
bean9 are boiled soft, with wheat or barley of equal 
quantities, and left for three months to ferment; 
salt and water are then added, when the liquor is 
pressed and strained. Good soy is agreeable when a 
few years old ; the Japan soy is superior to the 
Chinese. Large quantities are shipped for England 
and America. The Dolichos bean is much cultivated 
in Japan, where various culinary articles are prepared 
from it ; but the principal are a sort of butter, termed 
mico, and a pickle called sooja. 
» 
SALT INf TROPICAL AGRICULTURE. 
SALT — MANURIAL ALTJE — AUTHORITIES— JUDICIOUS AP- 
PLICATION NECESSARY — TODDY-DRAWING— INCREASED 
YIELD— REASONS — FUMIGATION— CARBONIC ACID— HOW 
FUMIGATION COULD BE OF USE. 
May 9tb, 1889. 
The last issue of your T. A. contains a good 
deal of information and discussion as regards the 
value of salt in agrioulture. The value of suit in 
agriculture is a subject on which opinions differ to 
some extent at the present day. The opinions of 
chemists and practical men have been taken and suited 
to support both views, viz., of its beiug geuerally use- 
ful in cultivat ; on ; and of its only beiug useful only 
in special cases and greatly injurious in others. The 
former view is held mostly by practical men who deal 
directly in agriculture, and deserves attention. Any 
good thing beyond a certain limit cannot be useful, and 
such is the case with salt. It is beyond any doubt of 
salt being a hygroscopic substance , thereby absorbing 
moisture and other gases, a solvent which makes other 
materials useful, an insectide which destroys the 
iujurious insects and prevent them from attacking 
crops, a substance which removes sourness in soil and 
helps the growth of plants, and last not least an actual 
constituent of cultivated plants. With such a list to 
its credit salt cannot be otherwise but a useful substance 
for vegetation. If salt is found in sufficient quantity in 
soils, it is uo use adding it to such lands. It is not the 
case with salt alone, but wi'h an) and every substance. 
If they be already present, it is useless to add them. 
But in the case of salt we should be particularly care- 
ful, as if we add more, instead of its being useless, it 
might prove to be injurious, unlike most other sub- 
stances. Prof. J. J. Manley in an article written by 
him on the salt industry speaks of its rnaiiurial value 
as follows : — " It is also user! as a manure for land, an 
ancieut practice in vouge in Palestine and Chiua more 
than 2000 years ago. At. the present day there is still 
much questioning as to the use of salt as a manure which 
has arisen partly from ignorance as to its chemical actiou 
and from its 'injudicious application. The tact also that 
it is speedily destructive of weed when used in certain 
quantities has helped to keep up a prejudice against it. 
However, by scientific farmers its use is well recognized, 
and each year it seems that a larger quantity is beiug 
demanded for agricultural purposes." (The italics are 
mine to mark the popular ideas which have prejudiced 
its use.) The same authority cites that '200,000 tons 
of salt a'e annually u^ed as manure in the Unite 
Kingdom. Apart from its value in regard to the im- 
provement of soils, both phjsically and chemically, salt 
is generally spoken as a good fertilizer for root crops 
and cereals. Thereforean applicatiou of salt — especially 
to such a hardier tree as the cocouut — iu cue inland dis- 
tricts where thoy haven t got much in the soil must 
be of very great use. The physical aud chemical im- 
provement of sal . s, which result from the application of 
salt, are marked iu warm and dry soils. Prof. W right- 
son, while speaking about salt, says, as regards its 
beneficial action on sour soils " that it may be used 
with good effect in pastures which carry a coarse herb- 
age." The cause of a coarse herbage is mainly due to 
a sourness of the soils, and we have a good deal of sour 
soils in Ceylon both in the form of some cultivated and 
neglected lowlands. The experiment is worth while a 
trial, and salt issued at a less price to bring such ne- 
glected lands into bearing. The application of salt should 
be judiciously done. Dr. Johnston advises applying it 
either as a top-dressing at the rate from one to jive 
hundredweights per acre, or using it mixed with water 
iu staking lime for application to lands. He says : 
" When applied to grain crops, common salt almost al- 
ways increases the weight per bushel of the grain when 
reaped mixed with quicklime and put on the land it 
gives strength to straw." 
Salt if judiciously applied to lands should form a 
good fertiliser to most of our inland soils. Whilst a 
few hundredweights of salt per acre wonld ensure 
increased crops, a ton if applied might instead of giving 
increased yield spoil the whole crop. 
While speaking of salt principally, if we at al] find it 
useful, we should look for good results to the inland 
districts. 
Some of the coconut plantations in the coast between 
Kalutara and Galle are entirely devoted to the drawing 
of toddy, and those trees appear healthier than the 
rest. There was a question once whether toddy draw- 
ing increases the production of fruit, and your Siyane 
Korale correspondent had a given list of chemical analysis 
of the products of the tree. I myself have observed 
and agree with him that trees after toddy drawing 
produce better crops. It cannot be owing to any stimu- 
lating effect as mentioned iu a note thereto ; if so, the 
vigour of the tree would have to be sacrificed for the 
better crop, but it is not the ca~e here. Trees which 
are devoted to toddy drawiug, show forth a vigorous 
growth than the rest. It is a common belief amongst 
the goyiyas, that coconut trees which do not produce 
well, would be improved by this process, aud so they 
in many cases have resorted to the process of drawing 
sweet-toddy, more for the sake of improving the trees 
than for the syrup obtained. When we refer to the 
analysis of the products, we find this quite practicable, 
as a tree would not loose so much mineral matter 
when used for toddy drawing as from the ordinary 
way of cropping fruits. The amount of the yield of 
toddy per tree for one year is calculated at about 
63 gallons, and the mineral matter containing in tbem 
would amount to nearly 1,155 grains, whilst the average 
produce of tree consumes nearly 12,204 grains of mineral 
matter, or nearly eleven times the quantity consumed 
by the t>ddy. So it is quite clear that a tree alter being 
operated iu this way for a year would consume only one- 
eleventh part of what is required to bear an ordinary 
crop. Hence the increase cannot be owing to any 
stimulating effect produced by toddy drawiug, but 
actually by a process of great saving of mineral matter, 
a part of which goes to strengthen the tree and the 
rest in the plenteous production of fruit. 
The question of fumigating coconut trees was brought 
before the notice of the public by " Old Planter " in one 
of your issues, and at the same time casting a slight on 
the Agricultural School on some hearsay information 
which was at once reputed by " O. D." putting to riaht 
the opinion of " Old Planter." The question is, has smoke 
to do anything at all in improving a coconut tree ? it 
has no direct effect as some people believe in yielding 
more carbonic acid for plants. No person aspiring to 
know the scientific theories of plant life would ever be- 
lieve ; aud it is like the same as the human voice theory. 
When we put aside the question of carbonic, aci 1 we 
find some uses resulting from this process. Fumigation 
acts in destroying a deal of fungi aud iiisecis which 
live upon the leaves. Apart from carbonic acid, smoke 
contains traces of ammonia, nitric acid, and water 
vapour which are absorbed by leaves forming a good 
plant food. These two i easons are in themselves enough 
to account for the action of fumigation ou trees, aud 
when the materials for the purpose is available, and is 
of no use in any other way, smoking would do well 
in improving trees. W. A. D. S. 
