354 
THE TROPICAL AGRICULTURIST. [November i, 1887. 
it at once neutralizes the arsenic. For arsenic taken 
internally, take a tea spoonful of the oxide of iron; 
it is perfectly harmless, and more or less may be 
taken as the occasion requires. — Indian Engineer-. 
■ ♦ 
THE COLLECTING AND CONSERVATION 
OF RAIN-WATER FOR THE PURPOSE 
OF IRRIGATION. 
Works of this character are not infrequently re- 
ferred to in the accounts of the earliest historians. 
Herodotus describes the immense reservoir of Moeris 
as formed for the storage and control of the river 
floods of Nile-nourished Egypt; and of another, con- 
structed by Nebuchadnezzar, at Sippara, of 140 miles 
in circumference. There is no question as to the 
existence in the East at the present day (and es- 
pecially in India and Ceylon) of the remains of 
what may correctly be termed stupendous works ; 
and the date of the construction of which, as regards 
India, is in many cases pre-historic. In Spain, also, 
the Moors (whose occupation of the peninsula ter- 
minated in the 13th century) have left dams of great 
magnitude, situated mostly in the south-eastern pro- 
vinces of Murcia and Alicante, many of which are 
still serviceable. The reservoir at Tibi, 16 miles north 
of Alicante, is formed by an embankment of lime- 
stone rock built across a gorge or gully, the height 
being 135 feet, and contains 130,650,000 cubic feet 
of water, which is sufficient for two irrigations or 
soakings of soil per annum at the most needful periods. 
The extent of land thus available being about 9,150 
acres devoted to the cultivation of vines, olives, fruit, 
cereals, and other market produce; which, in that 
dry part of the year could only be reared by irrig- 
ation ; and the appearance of the area (over which 
the water can be conducted) forms a pleasing con- 
trast to the general aridity of the surrounding dis- 
trict. In the Planter and Farmer of September, 1882, 
on page 236, an account is given of a modern irrig- 
ation work in Hindostan, called the Ashti Tank, then 
just completed at Sholapore, near the Great Indian 
Peninsula Railway. The Times of India speaks of the 
reservoir as an important addition to the means of 
irrigation, and says that two canals start from outlets 
in the dam, each being 15 miles in length, and well 
able to water a total area of 25,270 acres of land. 
The entire cost being 6| lacs of rupees ; and the 
revenue calculated to yield 4 per cent, on the outlay. 
The earthen bund or bank to confine and act as a 
fence against the water, is 12,709 feet long, and 58 
feet high, and when full the tank will have a surface 
area of about four square miles, and hold 1500 millions 
of cubic feet of water, each cubic foot being equal 
to 6J gallons. 
In India and Ceylon the greater number of the 
ancient dams or bunds are now in ruins. There still 
exist, however, in the Madras Presidency, a not in- 
considerable number of ancient bunds, which serve 
their intended purpose at the present day as well as 
ever. Mistakes occasionally occurred in their con- 
struction, as is proved by the remains of some such 
works in Ceylon, where the failure was evidently due 
to an error in taking the levels. Among the most 
remarkable of these nucient works is the Horra-Bera* 
Tank, the bund of which is between 3 and 4 miles 
long, and from 50 to 70 feet in height; and, although 
now in ruins, would formerly impound a reservoir 
lake of from eight to ten miles in length, and from 
three to four miles broad. There is also the Kala- 
"Weva Tank, with a bund of 12 miles in length, which 
would, if repaired and rendered perfect, create a 
lake of 40 miles in circumference. Both of these 
ruined works are situated in Ceylon. f The third 
embankment of a similar character is that of the 
Cummum Tank, in the Madras Presidency, and which, 
although ranking amongst the earliest works of Hindoo 
history, is still in such a condition as to fulfil its 
* Horaborawewa. — Ed. 
t And both have been repaired. — Ed, 
original intention. The area of this reservoir ia about 
15 square 'miles, the dam being about 102 feet high, 
\ with a breadth at the crest of 76 feet. The bye-wash 
is cut in the solid rock, altogether clear of the dam ; 
but the outlet culverts are carried under the bank. 
Earthwork, in some instances combined with masonry) 
was a form of construction usual in the ancient works 
of the East already referred to ; but it would appear 
from the experience of recent years that masonry 
dams are likely to become as common as those of 
earthwork, in districts where the natural ground is 
rocky, and good stone easily obtained. The Velmi 
dam at Bombay, 95 feet in height, has a wall of clay 
puddle in the middle of it 10 feet wide at the top, 
with an increased thickness downwards of 1 in 8. The 
Oued Meurad dam in Algeria, which is also 95 feet 
high, was constructed with earthwork 23 years ago. 
And as the bank was carried up, water was admited, 
and allowed to rise to nearly the temporary crest of 
it, and as soon as the earthwork had settled the work 
was proceeded with and the same process repeated. 
At page 67 in the Planter and Farmer, of March, 1882, 
and on page 120 of that of May in the same year, a 
description is given of many other Indian reservoirs, 
and also various particulars as to the use of the water 
for irrigating the land, &c. — Spectator. 
+. 
Cocaine. — The demand for cocaine as a local anaes- 
thetic has had an effect on the export of coca 
leaves from Peru, the quantity sent from Mollindo 
during the past year being 705 quintals, of the value 
of 17,625 dols. —English Mechanic. 
South American Cinnamon. — The American Druggist 
says that at the exhibition of South American pro- 
ducts held at Berlin in the early part of this year, 
some cinnamon bark was exhibited, which Professor 
Tschircu considered fully equal in aroma and sweet 
taste to the Ceylon cinnamon. It was in pieces about 
2 inches broad and $ inch thick. The essential oil 
prepared from it by Tschirch could not be distin- 
guished from that of the Ceylon bark, though the 
yield was inferior. This is due to the fact that the 
pieces are taken from older branches which have a 
bark rich in 6toue-cells and therefore poorer in oil- 
cells. It is very low in price, and should have a pro- 
mising future. — Planters' Gazette. [If it has, it will 
to the further depression of the trade in fine Ceylon 
cinnamon, which even now is scarcely remunerative. 
-Ed.] 
Rhea. — Mr. Charles Maries, of the Durbhunga Raj, 
has tent us a specimen of Rhea fibre manufactured 
under his newly discovered process. The fibre is 
soft, silky, and clean, although Mr. Maries says " it 
is only a bit of refuse, not picked out." He adds 
further, that ho has now got over all difficulties, 
and can turn out the fibre in a much simpler way 
than that described by Mr- A. Sansone, Director of 
the School of Dyeing in the Manchester Technical 
College, in an article reproduced by us last week 
from Bradstreefs. This is a very important step gained 
by Mr. Maries, and one which will, we hope, solve 
the Rhea difficulty in India. We are, of course, 
not aware what method Mr. Maries adopts in strip- 
ping the fibre from the stem — whether by hand or 
machine, or the cost at which it is done ; but we 
have his assurance that it is of the simplest kind, 
and very cheap. We would suggest some of our 
large textile firms putting themselves in communic- 
ation with Mr. Maries with the object of coming to 
some arrangement to work up the Rhea on a large 
scale. Messrs. Ewing & Co. have so far taken the 
initiative of inviting tenders for the supply of the 
stems. We have little doubt that Rhea is destined 
to mark an epoch in the textile industry of this 
country ; and if Mr. Maries' process proves to be 
all he claims for it, quite a revolution may be ex- 
pected in the fibre- trade at no distant date. — Indian 
Agriculturist. [Yes: "if Mr. Maries ' process prove 
to be all he claims for it," which only a full and public 
trial can show.— Ed.] 
