1830.] 
On Indigo. 
207 
2do. One feeder canal to be excavated from Chitpur to the West- 
ern Lake ; the floor at its river mouth excavated to -1- 2, which will 
require 16 feet of digging. The floor at the Lake end at 0 , or perhaps, 
*4-, 1 to he 27 feet or 25 broad at bottom, and trapezoidal, so that 6 feet ot 
water may give 200 square feet average section oL such an excavation 
being 530 square feet, will cost 7,680 Rs. per mile, for length of 3 miles, 23 040 
3to. Three bridges will be necessary over this canal, for the several 
roads ; to each bridge I would provide some contrivance for closing the 
canal, estimating each at 15,000, 45 000 
4to. Sundry expenses for preserving a channel as fast as the Lake 
may fill at the place of discharge from the feeder canal ; as also in em- 
banking the side towards the discharge canal, when sufficiently raised, 
also the western side, and watching the place of discharge, 15 000 
Supervision and contingencies, 4 332 
• 5to. Add the compensation for the acknowledged rights of fishery 
and incomes now enjoyed upon the faith of the rights conferred by 
the perpetual settlement, (estimated at 1 lac of rupees for the whole lakes,) 
for the Western compartment, 30 000 
Total expense and outlay, 1 20 972 
N.B. The above does not include any charge for purchase of ground 
for the feeder canal, and provides only a single feeder. It will be possi- 
ble, I believe, to find ground from that purchased for the circular canal, 
without any very material sacrifice in the resale of ground from which a 
certain return is calculated upon. 
As per contra to the above : — 
The contents of the Western compartment of tbe Lake are 10 630 
begas of land, tbe value of which nett, when fit for cultivation, may be 
taken at the least 30 rupees per bega, yielding, 3 18 900 
It would be easy to shew that the recovery of the second compartment, in sur- 
face upwards of 12 000 begas, would be still more profitable in return, as it would 
be free from the great expense of excavation near Chitpur and bridging the canal. 
With an additional outlay of 50 000, this second compartment would yield 
a return of three lacs ; but as this part of the undertaking is remote, I wave any 
further remarks on it in the present paper. 
II . — On Indigo. By Andrew Ure, M. D. y F. R. S. 
[From the Quarterly Journal of Science, No. XIII. N. S.] 
Among the vast variety of vegetable products, there is probably none so inter- 
esting to Science, by the curious complexity of its nature, and the protean shapes 
it may be made to assume, as indigo $ and certainly, there are few more impor- 
tant to British commerce and enterprise, since it constitutes the most valuable 
article of export and remittance from Hindostan. At the four quarterly sales 
appointed by the East India Company, no less than 20 000 chests of this dying 
drug are, on an average, brought annually into the market. A very considerable 
quantity of indigo is also imported into Europe from America and Egypt. It is 
not long since the Caracca and Guatemala indigo held a much higher character, 
and commanded a much better price than that of India ; but the improvements 
due to the intelligence of our planters in the East, have, within these few years, 
enabled them to prepare an article very superior to the finest American. The 
sequel of this paper will present satisfactory proofs of this assertion. 
Indigo is procured from many different species of plants, belonging to Tourne- 
fort’s natural family of Legziminosa, included, for the most part, in the genus called 
Indigofer a by Linnaeus. According to Heyne, the Indigofera pseudo- tine t aria, 
cultivated in the East Indies, produces the best indigo ; but others extol the Indi- 
gofera anil, argentea , and disperma , which yields the Guatemala kind, and some 
the niexicana. About sixty species of Indigofera are at present known ; but those 
abovenatned are in peculiar esteem. My object in stating these differences here, 
ia chiefly to show that a drug obtained from such a variety of vegetable species, 
must necessarily vary in composition. The matter which affords the indigo, is con- 
