Aug. 1. 1899.] Supplement to the Trnjncal Agricidturifst.'" 
145 
The Kola from Gaudja, which is of a uniformly 
red colour, is the one most frequently brought to 
Kavo (the capital of Ceutrnl Soudan), as it keeps 
better than any other. The most minute care and 
attention on the part of the merchant are necessary 
in order that the Xolas may reach the market in 
good saleable condition. They are carried for the 
most part in Kavo-made baskets, each of which 
contains 3,000 or 4,000 Kolas, whilst two of them 
form a donkey -load. If treated with the utmost 
care the nuts may be preserved fresh for 2 or even 
3 years, but in order to secure this tliey must be 
kept constantly damp. If exposed to the air and 
allowed to dry the Kola opens along the black line 
mentioned above, wrinkles, and becomes as hard 
as wood. In this condition it has lost 90 per cent of 
its value. During the march the nuts are packed in 
baskets and covered with fresh green leaves. Every 
4 or 5 days they ought to be repacked, in order 
that the leaves may be renewed and that the nuts 
which are touched with mildew may be removed. 
The large profits obtainable on the sale of those 
•which reach the various markets in good condition 
compensate for the risk &ud trouble of their 
carriage. At Gandja the average nut costs o 
cowries ; at Say, on the Middle Niger, 70 to 80 
cowries; at Sokoto, 100; ut Kavo, 140 to 250; at 
Kuka, on Lake Tchad, 250 to 300. 
What, then, one may naturally ask, are the 
peculiar virtues of this fruit, which forms by far 
the most important article of commerce in the 
Central Soudun ? The fact that for generations 
past it has been eagerly sought after by rich and 
poor alike, and that men will constantly spend the 
last cowries they possess in buying one to chew, 
seems clearly to show that it is something more 
than a mere luxury. The scientific analysis of the 
nut shows the existence of a large quantity of 
tannin and of an alkaloid analogous to theine and 
caffeine. The natives believe that it keeps off the 
pangs of hunger and enables them to work for 
long periods without food. As a stimulant, it 
takes the place which tea and coffee with us, both 
of these being practically unknown. Owing to its 
extremely bitter and unpleasant taste, we were 
prevented from giving the sustaining power of 
Kola a fair trial. On the occasions, when, through 
lack of food we would gladly have made tlie 
experimeut, we were unable to obtain the nut. 
Whatever its real virtues may be, it is certain that 
the commercial value of Kavo is to a very large 
extent dependent upon the millions of Kolas which 
its market contains. 
On one occasion I met a caravan consisting of 
about 1,000 men, together with a large number of 
donkeys carrying Kola nuts up towards Kano. 
The value of the nuts in the caravan, which was 
only one out of several that annually came to 
Kavo for the same purpose, was Nttle less than 
£100,000 sterling. The whole of this immense 
trade is at present in the hands of natives, as the 
course of the Niger is not such as to allow of the 
Kolas being carried by water any part of the way. 
[The name of Mr. J. P. Williams, the well-known 
Seedsman of Henaratgoda, is always associated 
with Kola nut in this colony. Mr. Williams sent 
some excellent specimens of dry Kola nut to the 
Colombo Agri-Horticultural Society Show held last 
month.— Ed. AM-I 
A NEW SYSTEM OF SOIL CULTURE. 
This is the title of an article in the Rural 
Californian, in which a great deal is written in 
praise of Mr. H. W. Campbell, the originator 
of the so-called new system of soil-culture. We 
would quote the following which is given as 
part of a report of the Northern Pacific Railraod 
Company, to give some idea of ^;he new system 
referred to ; — 
"The Campbell method consists in a complete 
re-arrangeraent and pulverising of the top seven or 
eight inches of soil, and turning it as nearly bottom 
upward as possible. The plant food in the soil is 
found at the end of each season very largely con- 
centrated in the top four inches. This plant, food 
must be ploughed down into the bottom of a furrow 
seven or eight inches. From this depth it will be 
placed by the action of moisture, just where the 
little feeders of the plant roots want it. Immedi- 
ately after ploughing, the lower four inches of the 
furrow-slice must be packed as firm as possible, 
for four important reasons : 
"1. To completely obliterate all cavities. Where 
the furrow lies loose, the air circulates under the 
plants and the ground dries out. It must not be 
permitted to do this. It is ruinous to the crop. 
"To cause moisture to gather from six to eight 
inches from the surface. Why? Because the 
stubble and manure, and other vegetable matter, 
is there, and water is necessary to rot it and fit it 
for the food of the crops. Unless this is done, the 
plants are robbed of their moi<t valuable food. 
" 3. To get the right conditions for rapid root- 
growth in the early part of the seiison. For this 
a fine, firm, moist soil must be had. The lower 
part of the furrow-slice is the root-bed, and must 
be kept in just the right condition if we are to get 
a rapid and vigorous root-growth. 
"4. By firming the root-bed we hold more 
moisture. More than this : The pores in the ground 
are made so small, that the water creeps through 
the soil readily by the force called capillary attrac- 
tion. By increased capillary attraction moisture 
is drawn more rapidly and from a greater distance. 
This gives the plant food and drink at critical times, 
when the weather is hot ; when the hot winds blow, 
and when the evaporation from the leaves is 
greatest. Your crop never suffers at such times if 
there is plenty of water for the roots. But a 
shortage of water at that point may ruin your 
whole crop in a day." 
Large increases in crops are reported as the 
result of actual experiments carried out on the 
lines of this system. We shall refer to this 
subject in a future issue. 
ORIGIN AND FORMATION OF ORGANIC 
MATTER IN PLANTS. 
By the ordinary method of sand culture, in 
which the plant is grown in sand free from orcranic 
matter, it may be demonstrated that the pluut 
accumulates considerable quantities of carbon and 
nitrogen during its growth. Tliis carbon and 
nitrogen with the elements of water form the or- 
ganic constituents of the plants, which with a 
small quantity of mineral ingredients make up the 
