1844.] 



of a Pier at Madras, 



59 



These sluices, after making the necessary excavation to enter, are 

 proposed to be guarded from the surf, and south-west winds, by two 

 embankments formed in the most solid manner of piles of earth and 

 stones, as expressed in the plan, and to be carried out to the distance of 

 four hundred and fifty yards, each, from the shore, to the depth of 

 fourteen feet low water, and at their extremity towards the sea, open to 

 the extent of two hundred yards, as under. 



In the general plan No. 3 is exhibited the relative situation and extent 

 of the sluice and embankments, and from an inspection of these two 

 plans,' the operation of both, and the nature of their construction will be 

 readily understood. 



By these means, I conceive a safe and easy passage may be obtained for 

 all vessels within twenty feet beam, and not drawing more than six 

 feet water at the lowest tides, though when the tide is in, those of even 

 nine feet draught of water within the above dimensions of beam, may 

 freely *be admitted, and the actual advantage of a harbour may be pro- 

 cured to all vessels of under fourteen feet draught of water within the 

 two embankments, where there is sufficient space secured for the entire 

 number that may be supposed at Madras at one time, to anchor in per= 

 feet safety, and even to come ashore from them along the embankments, 

 without expence and delay of boats. 



The effect of the sluices affording a water way of one hundred feet 

 wide with a fall of, in ordinary tides, three feet perpendicular height, 

 when all the gates are opened at the same time, may be easily conceived, 

 and the constant daily repetition of this process, will, I imagine be readi- 

 ly allowed, to be sufficiently powerful to carry, off any deposition of sand 

 that may be formed. 



With regard to the practicability of executing this work, it will be seen 

 at once, that in constructing the set of sluices, the work is nearly the 

 same as that of building the counter scarp wall of the sea face of the Fort, 

 and. the instance already quoted of the late Mr. Baker's piles, is sufficient 

 to increase the possibility and effect of that part of the business ; the 

 rest of the work then requires no particular ingenuity, being nothing- 

 more, than carrying stones and earth to the spot, and throwing them in. 



Concerning the effect of the backwater, should it be doubted that it 

 would be sufficient for the purpose intended, it would be easy to introduce 

 the use of ballast lighters to their aid, the work of two of which, at an 



