On the Physical Features on Adam's Bridge and The

23 Janll:Lry, 1917. SiI, MAURICEFITZMAURICE, C.M.G., President, in the Chair. (Paper No. 4195.)

“ On the Physical Features of ‘Adam’s Bridge ’ and the Currents Across it, considered as affecting the Proposed Construction of a Railway connecting Indiawith Ceylon.” By FRANCISJOHN WARING, C.M.G., M. Inst. C.E. THE subject of this Paper is, it is thought, sufficiently indicated by its title, and in the latter portionof it the Author will refer, in the hope of eliciting discussion, tothe vnrioas methods which have Ileen proposed for c:trrying out the connection in question. Aplrrtfrom its conmerc:i:d and possibly st,rategic import’ance, the work presents unnsnd engineeringdiaculties, due to its n~xgnitnde,tjhe strength of thecurrents at timesprevalent, and other 10c:tl conditions.Nevertheless, in view of the recent extensions of theSouth Indim Rai1w:Ly to Dhanushkodi, theeastern point of Rameswaram Island,and of the Ceylon Government Railway to Tnlai Mannar,the western point of MannarIsland, leaving only “Adam’s Bridge” to be dealt with in order to complete the land connection between India and Ceylon, the commencement of the undertaking may possibly not be long delayed; and thus the light-draughtferry-steamers, by which communicationbetween Dhanushkodi and T;tLi Mannar is now carried on, may be replaced eventually by ;I railway. It shouldbe explained here that the railways *just mentioned bifurcate at Dhanushkodiand Talai Mannar respectively, and terminate in steamer-piers erected on the north and south coasts of the islands of Rameswaram andMannnr. It was intended originally that during the north-east monsoon the steamers would ply between the southern piers, and during the south-westmonsoon

between the northern piers, Adam's Bridge thus acting its a break- water,and ensuring a smooth sea-passage in bothmonsoons; it was found, however, possibly owing to the oceanic swell in the Gulf of Mannar, that the southern passage, even during the north-east monsoon, was more difficult than was anticipated, while during that monsoon the northern passage was less difficult than was anticipated, and, as a result, since 1914 the steamers have continuously used in both monsoons the passage to the north of Adam's Bridge. In the eleventhedition of the Encycloprerlia Brifannicn (1910) the article upon Ceylon states that:-

('The coast is beset on the north-west with numderless sandbanks, rock3 and shoals, and may be said to be almost connected with India by the islan(l of Rameswaram and Adam'sBridge, a succession of bol(lrocks reaching almost across the gulf at its narrowest point,."

' The impression thus conveyed is erroneous,as Adam's Bridge is a bank superficially of clean, fine, greysand, overlying, it is said, for a portion of its length, rock, which stretches in a fairly directline for about 21 miles between Dhanushkodi, atthe eastern extremity of Rameswaram Island, off the coast of India, and Talai Mannar, the western extremityof Mannar Island, off the coast of Ceylon. With the islands just mentioned and the channels (comparatively narrowand generally shallow) between themand the countries to which they respectively belong, this link between India and Ceylon extends in a fairly straight line from Toniturai orRaman Point in India(north latitude 9" 17', eastlongitude 79"11') for n distance of 55 miles in an east-south-east direction to Taladi, in Ceylon (northlatitude 8" 56' 30", eastlongitude 79" 56' 30"). It not onlysuggests in an emphatic manner theonly practicable route for a connectionby land between the twocountries, but also divides the channelbetween Ceylon and India very definitely into two parts of widely different character (Fig. 1, Plate 6). The southern part of this channel, known as the Gulf of Mannar, is an arm of theIndian Ocean of generallyregular outline. Its entrance, facing south-west, has :L width of 180 miles between Cape Comorin and Colombo, taperinggradually to 55 miles between TonituraiPoint and Taladi. The gulf is of considerable depth, nearly1,200 fathoms being found about midwaybetween Cape Uomorin and Colombo ; about 50 miles north of this a depth of 1,247 fathoms occurs about 40 miles from the coast of Ceylon, while even within 17 miles south of Adam's Bridge a sounding of 150 fathoms failed to reach the bottom.

The northern part of this channel, known as Palk Strait, is, on the contrary, of irregular outline, and is very shallow, the depth over the greater portionof its extent beingbetween 6 and 8 fathoms. A greater depth than 9 fathoms is nowhere found, and even that occurs only in onespot of smallarea. Immediately to the north of the direct line between Toniturai Point and Taladi the width of the strait is increased, mainly by the westerly trend of the Indian coast, from 55 miles to about 84 miles. This width is maintained without much alteration for some 34 miles northwards, when by the westerly trend of the Ceyloncoast and the islands lying off the north-western point of Ceylon, the width of the strait, which then turns to the east, is reduced to about 40 miles, a width approxi- mately maintained to its entrance, which faces north-east and lies between Point Calimere, in India, and Point Pedro, in Ceylon. The physical features of bothparts of the channel,including their entrances, which it will be observed face directly the prevalent monsoon winds, have, in the Author’s opinion, an important bearing onthe currents existing at Adam’s Bridge : hencehis reason for mentioningthem. The whole of the channelbetween India and Ceylon lies inthe region of the south-westa,nd north-east monsoons, the former usually setting in about the latter part of May, or early in June,and the latter in October or November. Both monsoons blow with greatest force at their outset, and strong winds from the respective directions blow steadily for some months ; as each monsoon progresses the wind gradually becomes lighter, and generally towards the end of each monsoon it has but little strength. The effect of these winds blowing steadily from the same direction for considerable periods is to raise the water-level on the windward side of Adam’s Bridge, and to withdraw it from the leeward side. Coupled withthe non-synchronism of the tides, this causes a maximum difference of about 18 inches between the water-levels on thetwo sides, thegreatest effect beingobserved, it is believed, during the north-east monsoon, due possibly to the configuration of Palk Strait, to which reference has just been made. The breadth of the base of Adam’s Bridge reckoning from the 7-fathom line on either side-that being the usual depth of Palk Strait in theneighbourhood-is generally about 10 miles, but owing to a southerly extension of shoal water towards its eastern end it is there somewhat wider. The sand of which it is superficially composed extends to a depth of at least 25 to 30 feet below sea-level, as disclosed by borings taken by the Author in 1895, the tackle at his disposalpreventing greater depths from being reached.Borings taken in 1913 by the late Mr. J. T. Lewis, M. Inst. C.E., Chief

Engineer of the extension of the South IndianRailway to Dhanush- kodi, disclosed rock for a distance of 15 miles from Dhanushkodi, at a depth ranging between 29 and 41 feet below mean low-water level, but, eastward of this the rock dips, and none was found at a boring carried to a depth of 36.60 feet below mean low-water level. From Dhanushkodi the general direction of Adam’s Bridge for the first 11 miles of its length is abouteast-south-east ; it then graduallycurves to the north, and for thelast 5 or 6 miles its direction is somewhat north of east.Along its crest, which generally occupies a central position with regard to its base on either side, as defined above, thus giving, reckoning from sea-level to the 7-fathom line, an average transverse slope of 1 in 628 on each side, R chain of several sandbanks above sea-level occurs, the channels between them being sometimes of considerable depth. The author found 34 feet in one of them in 1895, while Mr. Lewis found in 1913 a depth of upwards of 42 feet in a channel about 4 mile from Dhanushkodi;speaking generally, the narrower the channel the greater is its depth, and through these channels the current runs in the direction of the prevailing monsoon. It has been estimated, not only by Mr. Lewis but also by Mr. H. J. Strscey, M. Inst. C.E., Chief Engineer of the extension of the Ceylon Government Rail- way to Talai Mannar, both of whom had ample opportunities for observing it, that when the monsoons are blowing with their greatest force andthe difference of the water-level on the twosides of Adam’s Bridge is at its maximum, the velocity is about 6 miles per hour; and in fact at such times Adam’s Bridge,with the islands and the channels separating them from the mainland on either side, appears to act as a weir. It must not be inferred from the depths of the channels between the islandsforming the crest of Adam’s Bridge that any of them are navigable, except by canoes and boats of very small draught, and even these can pass through only with difficulty and some danger ; for the water, which when the head and velocity are greatest isvery turbid, being heavily charged with sand in suspension scoured out of the channels, begins to deposit it as soon as the head is lost and the currentslackened, in effect forming a bar below each channel. Thus, in March, 1895, towards the close of the north-east monsoon,when the wind and current were but slight, the Author found on the southside of the crestopposite even the deepest channels a maximum depth of only about 7 or 8 feet, on or outside which heavy breakers occurred. Mr. Lewis has described the channels in question as being in reality “ mere pot- holes,” While Adam’sBridge viewed as a whole isundoubtedly permanent, yet, in the Author’s opinion, the sandbanks above and

nearwater-level constituting its crest, and the clmnnels between them, are, within certain limits, continually changing according to the monsoons and their comparative strength. This is what might be expected, having regard to the effect of the monsoon winds and currents, to the difference of the level of thewater on the two sides, and to the fineness of the sand of which the upper portion is composed; and it is, the Author thinks, abundantly confirmed by the changes disclosed by thevwious surveys that have been carried out, to which reference will be made later. Although the tides,which are mainly dependent upon the strength of the wind, are so irregular that their levels on any particular day cannot be predicted,yet fromobservations taken during 1912 at the north steamer-pier at Talai Mannnr in Palk Strait, near the easternend of Adam’s Bridge, it would appearthat the daily range is practically uniform and about 1 foot 7 inches. There does not appear to be any difference in the range at spring- or neap- tides ; at any rate it is not 5wficiently marked to be distinguishable from the greater fluctuations in level of the whole body of water caused by the winds and currents. The greatest range between the highest high-water and thelowest low-water level registered during the year mentioned was about 4 feet 6 inches, the lowest low-water level being 1.15 foot below mean low-water level, and the highest high-water level being 1-75foot :hove mean high-water level. It will be well to refer briefly here to the channels separating the island of Rameswaram from India and the island of Mnnnar from Ceylon, as they may, perhaps, be not improperly viewed as being extensions of Adam’s Bridge beyond thoseislands. The former, known as the Pamban Pass, lms a breadth of about 2,260 yards :tt its narrowest point, where :L reef of rocks stretches across it ; along this reef the Dhanushkodi extension of the South Indian Railway iscarried by a viaduct. In the reef one narrowgap, deepened artificially, occurs, which affords the only passage whereby Ceylon can be circumnavigated by vessels other than canoes or small boats. Across this gap a Schemer rolling bridge for the railway has been built. The gap is not available for vessels with a greater draught than 10 or 11 feet. It has been stated that the difference in the level of the water on each side of the reef is sometimes as much as 15 inches, and that then the velocityof the current is7 miles per hour. The Mannar Channel or Straitis about 3 miles in width opposite to the townof Mannar, widening to the north and narrowing to the south, where its breadth is further contracted by the occurrence of two or three flat sandy islands, and it is, for the most part, tlry at low water. It is navigable only by canoes or small boats, being closed

Downloaded by [ University College London] on [20/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] ADAM’S BRIDGE AND THE CURRENTS ACROSS IT. 259 by a bar at either end. The extension of the Ceylon Government hilway toTalai Mannnr is carried across the Mannar Strait by an embankment the slopes of which are pitched, bridges being provided at the water-channels. In the Mannar Channel the current is also at times very rapid, but exact observations are wanting. The idea of a land connection between India and Ceylon is one of greatantiquity, the mythologicalorigin of Adam’s Bridgebeing stated in “ The RBmkyana,” an ancient Sanskrit epic poem. The first reference which the Author can find to the engineering question which forms the subject of this Paper is a document by Lieutenant-Colonel J. H. M. Shaw-Stewart, R.E., then Consulting Engineer for Railways to the Madras Presidency,who submitted to his Government, in August, 1876, a report on the proposed construction of a railway connecting India with Ceylon ; no action, however, appears to have been taken upon this report. It is noteworthy that thelate Sir Charles Hutton Gregory, Past-PresidentInst. C.E., withmuch foresight, recommended forthe Ceylon Government Railway, for which he was ConsultingEngineer, the adoption of the Indian gauge of 5 feet 6 inches, in view of the possible connection at some future time of that railway (the construction of the first section of which was begun early in 1863) with those of India. No furtheraction was takenuntil February, 1895, when Mr. E. I. Shadbolt, Engineer-in-Chief to the Madura-Pamban Railway Survey, paid a visit to the site and submitted a report’ to the South Indian RailwayCompany upon thematter. In the following month the Author, who at that time occupied the position of Chief ResidentEngineer for railway extensions in Ceylon, also visited the site and furnished a report to the Government of that Colony upon the question. In 1911 Mr. Lewis furnished a preliminary report to the South Indian Railway Company on the matter, which was supplemented by a more detailed report accompanied by a survey in 1913 (Fig. 2, Plate 6). In 1912 Mr.Stracey also furnished a reporton the question to the Ceylon Government. Lieutenant-ColonelStewart did notstate in his report how he proposed to construct a railway along Adam’s Bridge, but he remarked that it

“ would be an undertaking involving protective works upon a large scale in a locality where labour and materials would have to be brought from a distance.

“ Proposed Indo-Ceylon Railway : Note on the Construction of a Railway to connectIndia and Ceylon.” Colombo, 1895. . * “ProposedIndo-Ceylon Railway : Reportupon an Inspection of the Route, etc.” Colombo, 1895. [THE INST. C.E. VOL. CCIII.] U

\Vitlloutclose local examination it woulcl be imposailde to give even a rough sketch of the necessary works, butthere can beno doubtthat the cost of connecting Ramaswaram and Mannar by a line of railway would involve a very largeoutlay. In roughlycalculating this outlay at between $25 and &‘l0 per hedfoot, or, say, at f40,000 per mile, it is probable that the cost of this section is under-estimated.”

Mr. Shadbolt, whose acquaintance with Adam’s Bridge seems to have been confined to sailing along it once in each direction, “ the position of the visibleland being roughly laid down by taking observationswith a pocket compass andestimating distances by notingtime in connection withthe calculated rate of speedas- sumed,” a method which he admits ‘‘ is very partial and insufficient, but is betterthan nothing,” estimated that water “ extends for 12 miles, low land for 6 miles, and high land for 3 miles of the distance.” He assumed the range of tide to he 3 feet, and proposed the construction of a solid causeway carried on rubble mounds, the

hearting of the causewaybeing formed of sand (Fig. 3). Mr. Shadbolt proposed that formation-levelshould be 12 feet above high water, and his estimate for the work was Rs. 24,900,000, equal, at thepresent rate of exchange, to Z1,660,000. TheAuthor, whose visitin 1895 was madeindependently of Mr. Shadbolt’s-in fact, at the time hedid not know that that visithad been paid-furnished himself witha chart of Adam’s Bridge made from surveys by Lieutenants Powell and Ethersey, of the Indian Navy, in July, 1838, andMarch, 1839, the onlyone then in existence(Fig. 4, Plate 6). From that chart he observed that the changes in the sandbanks above water-level between those two surveys were in places very considerable, and in the interval that had elapsed since they were made the changes were so great as tonecessitate, in his opinion, n freshsurvey beforeeven an approximate estimate for constructing a railway could be arrived at, Thesandbanks abovewater-level, by the Author’sflying trigonometrical survey and the soundings taken between them, are

shown in Fig. 5, Plate 6. In makingthat survey he paid no attention to the stateof the tide, the range of which is only about 14 foot; the outline of the sandbanks and their area above water- level, as well asthe soundings, would thereforenaturally vary somewhat according to the stateof the tide when the survey of any particular sandbank was made and the soundings were taken. Being aware of the existence of a very rapid current, the’ Author considered it would be advisable to provide openings at all places where the depth of water exceeded 3 feet, as he believed that to encroach further on the channels would entail serious acceleration of the current, coupled, of course, with greater scour. As generally all heavy seas would break, owing to the shallowness of the water, at distances of upwards of 3 mile from the crest of the ridge along which he proposed the railway should be constructed, he considered that on the sandbanks and wherever the water was not more than 3 feet deep, the railway might be carriedon an embankment formed of sandfrom the s:tndbanks themselves, cased withclay brought from the mainland, to prevent the sand from being blown away, and protected by stone pitching to a height of about 4 feet above high-water level. Where the depth of water exceeded 3 feet he proposed tobridge the channels, and he estimated that the aggregate length of bridging required over them would be upwards of l0 miles. He further proposed thatthe ends of theembank- ments where they abutted on the various bridgesshould be of stone so as to protect them from scour, and that formation-level should be 8 feet above high-water mark. His estimate for a line on the 5-foot &inch gauge with rails weighing 46% lbs. per lineal yard was, without rolling stock, Rs. 25,500,000, equal, at the present rate of exchange, to ,C1,700,000. That estimate is to be viewed as being only a very rough and approximate one, and to be subject to such modifications :LS may be dictated by the further and detailed studies which would have to be made before construction was begun. Mr. Lewis proposed for the sandbanks above high-water level an embankment of sand, pitched with coral to prevent the sand from being blown away; and, believing that if the channels were closed they would siltup, he proposed to close all of themby a solid causeway formed of two rows of reinforced-concretepiles 14 feet apart in the clear, the piles in the two rows being opposite to each otherand securely connected togethertransversely at vertical intervalsby chain cables andby reinforced-concrete bracing between their heads,Longitudinally the piles in each row were to beconnected temporarily by cast-ironheads and chain cables, theseheads and cables being removed subsequently andconcrete U2

Downloaded by [ University College London] on [20/09/16]. Copyright © ICE Publishing, all rights reserved. 292 WARING ON THE PmsrcAL FEATURRS OF [Minutes df archesserving as a copingbeing substitutedfor them. The piles in each row were to be 10 feet apart, and their sections ranged from 10 inches by 10 inches where at high water the water is only 3 feet deep, to 15 inches by 16 inches where there is 10 feet at high water, to 16 inches by 16 inches where there is 15 feet, to 22 inches by 1G inches .in depths of 23 to 33 feet, and where the latter depth is exceeded, 264 inchesby 16 inches. Abuttingagainst the back of eachrow of piles, reinforced-concreteslabs 4 feet in depth, and ranging from 9 inches to 16 inches in thickness, according to the depth of water, were to beplaced. Thejoints between them were to be rendered watertight by cement, and the lower edge of the lowest of these slabs was to be bevelled to facilitate its entry into the sea-bed ; the space between the backs of the slabs was to be filled with sand. A typesection of the proposedcauseway in the deepest channels met with is shown in Fig. G (p. 293). Formation- level was to be 9 feet above low-water level. Mr. Lewis estimated that the cost of the work for a metre-gaugerailway with 50-lb. bull-headedrails laid on chairs with wooden sleepers wouldbe Rs. 11,091,814, equal, at thepresent rate of exchange, to 2739,454, and that this sum could be reduced by the sale of the steamers now running and the materialsfrom the steamer-piers. Mr. Stracey’sproposals are generally in accordance with Mr. Lewis’s, with the addition of wave-breakers in the deeper channels formed of heavy blocks of stone deposited in aline parallel to the causeway and a shortdistance therefrom. His approximate estimate for a line of &foot 6-inch gauge with rails weighing80 lbs. per lineal yard, formation-level being 9 feet above mean sea-level, was Rs. 9,234,944, equal, at Is. 4d. per rupee, to $615,663. Mr. Lewis differed from the Author in considering that some of the largersandbanks abovewater-level arepermanent, and he mentionsthe existence of vegetationon some of them. It is the case that at the Author’s visit some vegetation was found on some of the larger sandbanks, but it was of a purely littoral type, similar tothat foundon the shores of Ceylonimmediately above high water,and does not, inthe Author’sopinion, point tothe permanency of the sandbanks in the strict sense of the term, On some of the larger of them hummocks of wind-blown sand, possibly 20 feet in height, were found;but this fact also, in his view, affords no very decided evidence of the permanency of the sandbanks for more thana few years at most. Examination and comparison of the surveys of Adam’sBridge (Figs. 2, 4 and 5, Plate G), shows that, while the general direction of the line of sandbanks forming the crest remains fairly constant,

Downloaded by [ University College London] on [20/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] ADAM’S BRIDGE AND THE CURRENTS ACROSS IT. 293 theirdetails have varied so much that it is impossible to super- impose themsatisfactorily, inthe absence of any well-defined

Fig. 6.

DEPTH OF WATER 40.00’

-25.66

-40.00 G.L. 7

permanent marks which could beadopted asdatum points. The arrangement of thethree surveys,on Plate 6 bringsinto pro- minence not only theirsimilarities but also their differences,

points of which theAuthor waspreviously aware. Thusthe bearing of the extreme eastern point of Rameswaram Island from thepoint of junction ofAdam’s Bridgewith Mannar Island, according tothe surveys of Messrs.Powell andEthersey, the Authorand Mr. Lewis, are “l”,74” and 72” west of north,the distancesbeing 19.9, 20.5 and 18.75 milesrespectively. It will beseen, therefore, that while the bearingsagree fairly well, and the distance, as nleasured by the Author, a,grees after a lapse of‘ 57 years within 0-G mile with that obtained by Messrs. Powell and Ethersey,yet, after the lapse of a further 18 years only, the distance, according to Mr. Lewis, differs from the Author’s measure- ment by no less than 1e75 mile, a surprisingly large amount for which the Author can offer no explanation.

Mr.Lewis criticized theAuthor’s scheroe onaccount ‘l of tlle enormous expense involved ” both in construction and maintenance, and added that “ it is one which would be fraught with considerable anxiety and even danger, as unless t,he current bedestroyed the deep pot-hole of to-day may within certain limitsbecome the shdlow of to-morrow, and nice ver8a.” While approving of the principle of Mr. Shadbolt’s scheme, Mr. Tlewis pointed out that heavy rubble cannot be obtained within 120 miles of the site and tbd the sand hearting would gradually escape throughthe interstices of the

rubble at each rise and fall of the tide ; he added that the cost l‘ is prohibitive and places it outside the category of practicability.” It is believed that the difference in the level of the water on the windwardand leewardsides of Adam’s Bridge whichoccurs at times must be due to the pwtinl obstruction to free flow caused by Adam’s Bridge itself, by the islands of Rameswaram and Mannar, and by the shallowness of the channels dividing those islands respectively from India and Ceylon, and that if these did not exist, though a rapid current ‘might and probably would remain, no such marked and abruptdifference in thelevel of the water would appear. If this belief be correct, it would seem to follow that any increase in this obstruction mustbe accompanied by a corresponding increase in the difference of the level of the water between the two sides of Adam’s Bridge, until at last a state of equilibrium was established between the opposing forces of gravity on the one hand and the effect of the prevailing monsoon winds on the other. Consequently, if Mr. Lewis’s proposal were to be adopted, though theclosing of the first few channels dealt with might be carried out without much difficulty and at the estimated cost, yet as the work advanced the progressiveincrease inthe velocity of thecurrent, accompanied by greater scour dueto the increasedhead, would resu-It in a

Downloaded by [ University College London] on [20/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] ADAM’S BRIDGE AND THE CURRENTSACROSS IT. 235 corresponding progressive greater difficulty and cost in closing the remaining channels. It must also be remembered that if by the construction of the causeway the difference in the level of the water on either side of it be increased, the effect would extend to the Pamban Pass, andthe difficulties of navigationthere wouldbe increased, possibly to a very serious extent. Moreover,should the difference inthe water-levelon the two bides of the causeway be materiallyincreased, which perhaps is unlikely to occur, or should the silting-uphoped for hy its construction take place to a much greater extent on one side of it than on the other, it would be subjected to lateral stresses in addition to those imposed upon it by the passage of trains. From perusal of Mr. Lewis’s report it is somewhatdiilicult to arrive at the opinion he held regarding the superficial features of Adam’s Bridge: fromcertain paragraphs it would seem that he viewed some of the largerislands, at least, as beingpermanent, andhe refers to Messrs. Powell andEthersey’s chart in support of this view; while, in writing of the velocity of the current, he mentions the scour and the quantity of sandheld in suspension, and whencriticizing the Author’sproposals, he specially insists onthe instability of the channels, andtherefore inferentially of the sandbanksseparating them. The Author, on the other hand, as stated above, views Adam’s Bridge, as a whole, as permanent, but considers thatall its superficial featuresare continually changingduring eachmonsoon. He is of opinion,however, that by providing suficient waterway to deal with the existing current without increasing its velocity to any serious or dangerous extent, it will be found perfectly practicable to induce the water to pxss permanentlythrough the waterwaysprovided for it by the construction, if necessary, of training-bundssimilar in character to thoseadopted with success atthe largerailway-bridges inthe Punjab over the Sutlej, Beas, Jhelum and Chenab rivers, the beds of which are of sand or silt ancl are subject to constant change and much scour.

The Paper is accompanied by six tracings from which Plate 6 and the Figures in the texthave been prepared.

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