330 
THE TROPICAL AGRICULTURIST. [Nov. 2, 1903. 
IRRIGATION IN CEYLON. 
We are so accustomed to think of Ceylon as a 
tropical and mountainous country with heavy and 
frequent rainfall, that it will be information to 
most people to learn that in the northern, half of 
the island there are large tracts of country where 
the life of the natives is practically dependent 
upon irrigation. Such has evidently been the 
case in centuries past, juds^inp from the countless 
remains of itiigaoion works now bems; discovered 
and restored amongst the dease forests which 
conscitute the north centra! division of the island. 
These works date back— mony of thern— before 
the commencement of the Christian era, to a 
time v/hen Ceyioa was ruled by its" own Kings, 
and when probably the whole island was densely 
populated and cultivated with an intensity un- 
known to our European races. But from 700 to 
1,200 A D, waves of invasion swept over the 
country from India, and the natives were 
gradually driven to the southward into the hills, 
the invaders usurping their place on the plains of 
the north but unable to establish themselves in 
the centre. Through continuous warfare, and 
the consequent insecurity, these central areas 
became a waste, the tropical forest— ever ready to 
regain its hold where the hand of man relaxes its 
vsray — quickly grew up over the deserted villages 
and fields, filled up the irrigation trenches which 
had been kept open with laborious cave, over-rau 
the dams and tanks of the industrious natives, and 
threw its dense mantle over all the works of man. 
Now once more, under the great Pax Britannica, 
under the fostering and directing care of the 
British resident and the British engineer, the 
forest is being driven back, dams are being re- 
stored, watercourses reopened, and happy, busy, 
thoughtful humanity takes once more the place 
of nature red in tooth and claw. Moreover the 
railways are being pushed out into these reclaimed 
territories, so that in a noble and beneficent sense 
it may be said that what we have we hold, not by 
force of arms so much as by the double ribbon of 
steel, which was Ruskin's ai)omination, but which 
counts for so much today in security against 
famine and in the charm and variety of twentieth 
century life even in the remoter regions of the 
world. In such work accomplished in India, in 
Ceylon, in Egypt, indeed in every quarter of the 
globe, Britain will send down the ages her 
proudest monument of Empire. 
A LE.SSON FOR QUEENSLAND. 
But what has all this to do with us in Queens- 
land ? maybe naturally asked. Mr levers thinks 
it has a great deal to do with us ; for he holds 
that in the system of numerous small daras con- 
serving the water in creeks, and depressions 
throughout the country, we have the possibility 
of irrigating areas which, though not sufficient 
to keep alive our immense flocks and herds 
in time of drought, may yet enable us to 
preserve the more valuable portions of onr stock, 
and protect considerable areas from actual devasta- 
tion, Mr. levers is not unmindful of the dif- 
ference between Queensland and Ceylon in the 
cost of labour; but whilst this may influence the 
character of the work to be undertaken, he 
believes that what has been done there can also 
be done here, though perhaps in a difl'erent way. 
It is pointed out that in Ceylon wherever a 
small watercourse exists a cheap earthen dam is 
thrown across it, by means of which a body of 
water can be held back for irrigation and cattle 
supply purposes. No piling or stonework is em- 
ployed in the dam itself, but the earth is dumped 
into the sice of the dam from either side, and 
allov/ed to gradually consolidate, the face being 
kept at the natural batter of 2 ft. to one. Numerous 
dams of this character are built, some indeed 
being of very large size. The one safeguard re- 
quired is that the spill-way, or by-wash as it 
would be called here, is of sufficient capacity to 
prevent the water ever reaching the top of (lie 
dam. A large by-wash is provided at either end 
of the dam in the natural ground, anfl these 
channels are protected with stones or boards, so 
that they will not wash out with the rush of 
water in seasons of heavy rain. What frightens 
people in works ©f this kind, says Mr. levers, is 
the enoraious cost of the sluices, which require 
skilled labour in construction and erection, and 
highly skilled labour, too, because if the sluice 
leaks, the whole work is destroyed. In Ceylon 
this difficulty is overcome in the smaller dams in 
a very simple way. By means of a box and 
'* core " of suitable pattern, concrete pipes are 
made in short sections, and tapering at one end, 
so that they can be connected by simply fitting 
the small end of one into the large end of 
another. In addition to this a square block 
of concrete is moulded with horizontal and 
vertical bore, corresponding with the size of the 
pipe. The block is laid in the bed of the water- 
course inside the dam, and connected on the one 
hand with a line of pipes running out through the 
bottom of the dam to the irrigation channels, and 
on the other hand with a column of pipes rising 
above the level of the water inside the dam. 
Thus we have an L-shaped sluice, of which the 
concrete block forms the elbow. The vertical 
column of pipes is protected by upright posts. No 
valves aroused, for when water is required, all that 
is needed is to remove a section of the perpendi- 
cular series of pipes, and let the water in, This 
also admits of adjustment to the varying levels of 
the water, and is at the same time a simple mode 
of shutting off the water altogether, as nothing 
more is needed than to bring the top of the pipes 
abov'e the water level by simply adding additional 
lengths. In a large dam there are provided a 
number of these sluices. Tlie diameter of the pipes 
varies from six inches to eighteen inches at the 
top. It remains but to distribute the water over 
the fields, and this is done by means of contour 
channels in the soil. Mr levers considers that the 
timber dam of America, which is in reality a weir, 
would be cheaper in Australia, where good timber 
is comparatively plentiful and labour dear ; but 
from what he has seen and heard of Queens- 
land, he is quite convinced that great relief from 
drought is obtainable by this means and without 
any excessive outlay. 
It is interesting to learn that some of these 
earthen dams in Ceylon are reiilly of an extensive 
character. One of the ancient coustructions of this 
kind which has been restored is at the confluence of 
three streams, and is six miles across, having a 
maximum height in the centre of 70ft., and so wide 
as to accommodate three teams abreast. This 
work tlirows the water back for a distance of 
five miles, and feeds, an irrigation canal fif^y 
four miles in length, distributing water to numerous 
villages on either side. This great work was cons- 
tructed by a native king in 340 A. D. But it is not 
such gigantic works that Queensland needs. It is 
rather to realise what was the object of the ancient 
