Showing posts with label Sri Lanka. Show all posts
Showing posts with label Sri Lanka. Show all posts

Sunday, June 18, 2017

Shade Fishing from Catamarans in India

Catamarans, of the type used on the Coromandel Coast in India’s southeast and in Sri Lanka, close by across the Palk Strait, are subject to two kinds of misconceptions. The first is one of terminology. In its original meaning, kattu-maram (Tamil for “tied logs”) denoted a raft, not a vessel with two identical hulls, as the term is commonly understood. The erroneous transference of the term was probably made by an early European traveler who, being familiar with Indian catamarans, decided to call the twin-hulled boats he found in the Pacific by the same name, it probably seeming logical at the time to call any indigenous, non-European small craft by the same term. Henceforth, our use of the term will refer only to the raft.

The second misconception concerns the nature of timber rafts, which are commonly conceived to be rectangular, flat, and capable only of drifting with the current rather than being directed according to the boatman’s wishes. Catamarans are, specifically, shaped rafts of wood or bamboo, and they behave more like true boats than like the flat, rectangular platform upon which Huck and Jim floated inexorably down the Mississippi.

Model of a jangada
Model of a jangada (source). Click any image to enlarge.
In Water Transport: Origins and Early Evolution, James Hornell describes several varieties of catamaran on India’s east coast and in many other parts of the world. Such craft are still in use in some locales. We have written about the jangada, a Brazilian catamaran in current use, and one can easily find with a Google search contemporary images of catamarans of more than one type on Sri Lanka.

three-log raft "boat catamaran" from Sri Lanka
A three-log raft from Sri Lanka of the type called a "boat catamaran" by Hornell. (source)
Hornell also distinguishes between catamarans that are more or less boat-like. In the Sri Lankan type that he calls “boat catamarans,” the central of three logs extends below the outer two, forming a keel, while the upper surfaces of the outer ones are considerably higher than that of the central one, forming an inside space that could be termed a hold or cockpit. In contrast to this, he describes the “flying fish” catamaran of Coromandel, which is the main subject of this installment. While it lacks a keel, it has enough of a depression in its upper surface to have an identifiable “inside,” and it is considerably more shapely and boat-like than the common conception of a raft.

Seven-log flying fish catamaran of the Coromandel Coast
A seven-log flying fish catamaran of the Coromandel Coast

In Fishing in Many Waters, Hornell describes in detail the flying fish type and its use, which he observed in the Tanjore district. Pursuing flying fish requires sailing to deep waters as far as 25 miles from shore with a crew of seven and staying out for as long as three days. As such, the deep sea catamaran is a substantial vessel, averaging 30 to 35 feet long. They are built of seven main logs of light wood, dressed on all sides and tapering from back to front and from bottom to top. Curved logs are selected, so that, when assembled, the main section of the raft is an isosceles trapezoid in plan view, and dished both longitudinally and transversely.

The logs are lashed together with coir rope. At the forward end, says Hornell, “the completed craft becomes definitely wedge-shaped in plan after the addition of an elegant upturned prow of five pointed pieces cleverly jointed on to the forward ends of the seven main logs.” Another log is lashed atop the outermost log on the starboard side to serve as a working platform.

rig details of a Coromandel Coast flying fish catamaran
Coromandel flying fish catamaran, showing rig details

The two-masted rig is refined, although it looks crude as a result of the materials from which it is made. Short masts fit into sockets on the whichever outside log happens to be to leeward, hoisting lateen or settee sails. The head of each cotton sail is lashed to a long yard with a short downward-curving extension at the forward/lower end. The foot of the sail is lashed to a boom that extends only as far forward as the mast. Between the mast and the end of the extension-piece of the yard is a foot-rope. The sail, however, does not extend all the way to the forward apex of the triangle. Its forward corner or tack is cut off short, so that the sail has a very short luff.

There are forestays and backstays, and the halyards serve as shrouds on the upwind side. There is also a short strut lashed at its lower end to the windward hull log, and at its upper end to the mast, about three feet from the base. Hornell writes, “Even with these substitutes for shrouds there is always the danger of the masts and sails falling overboard should the craft be taken aback by a sudden change of wind; this, however, is of rare occurrence…so steady is the wind at the season when these craft are at sea.”

As to control lines, “Each sail is provided with a sheet and a vang or guy made fast to the upper end of the yard.” The sail can be furled by rolling it up around the lower boom, and by moving the grommet from which the yard depends down from the masthead onto one of a series of notches provided for the purpose.

To counter leeway, the raft has two large leeboards and a large-bladed steering oar, the attachments for none of which are described. Hornell gives the following dimensions for one raft of typical size:
LOA: 33 feet
beam at forward lashing: 4 feet
beam at aft lashing: 7 feet
forward yard: 29 feet
after yard: 21 1/2 feet
steering oar: 12 feet
forward leeboard: 10 1/2 feet
after leeboard: 9 feet
draft (boards up): 1 foot

The boat is equipped with paddles and oars for when the wind fails. Two dip nets, consisting of a rectangular piece of netting (measuring 5’6” x 4’9”) with its short sides tied to poles about 7’ long, are carried. The rest of the equipment is limited to spare rope, a jar of drinking water, a bundle of cooked rice, a scoop to throw water on the sails, and three large bundles of bushes or shrubs, the last of which are key to the curious method of fishing practiced.

The raft is sailed into deep waters until a shoal of flying fish is sighted. The raft is brought into their vicinity, turned with its starboard side to windward, and the entire rig is dropped. The bundles of shrubs are then thrown over the accessory log on the windward side. Each bundle is attached to a rope of a different length: 300 ft.; 180 ft.; and 60 ft. The bundles act like sea anchors, and with the raft’s shallow draft, it quickly drifts downwind of them. (A block of wood tied to each bundle acts like a float, but it’s unclear from Hornell’s description to what purpose, for it’s clear that the bundles of shrubs sink to different depths determined by the length of rope to which they’re tied.)

Flying fish are attracted to the bundles. After a large number of fish have gathered, one of the bundles is pulled in slowly and carefully. The fish follow until it is close to the raft, at which time the dip nets come into play. Each net is operated by two men, one per pole. The net is dipped into the water nearly vertically, then brought up under the fish and tipped back so that the fish fall into the boat – the whole proceeding being performed in silence so as not to disturb the fish who remain beside the shrub bundles. When that group of fish has been disposed of, the next bunch of shrubs is hauled in and the process repeated.

According to Hornell, the attraction that the bundles hold for the fish is neither their shade nor the expectation that they harbor small prey upon which to feed. Rather, the fishing occurs during the flying fishes’ spawning season, and the bundles replicate the bunches of seaweed upon which they normally deposit and fertilize their eggs. 

Large quantities of flying fish may be caught by this method over the course of two or three days. Fish that are not eaten fresh are sun-dried, but given the long distance that the rafts sail from shore, it often occurs that the catch may spoil before it reaches market.

Also in Fishing in Many Waters, Hornell describes a second method of “shade fishing” from catamarans done off the Coromandel coast near Madras. Although he does not describe the catamarans, they are different from those described above, and from the illustration appear to consist of only four logs and to be manned by just two men. Nor does Hornell identify the fish thus captured. Four catamarans must cooperate to employ the madi valai, what Hornell calls (but does not translate as) a “handkerchief net.”

shade fishing with four catamarans off Madras
Shade fishing with the madi valai net and four catamarans off of Madras

A long length of coir rope is made up with many strips of palm leaf between the strands, making a bushy appearance. (We presume the rope appears far bushier in practice than in the illustration.) One end is tied to a stone anchor or heavy bunch of turf; the other to a piece of light wood as a float. The anchor rope is dropped in “several fathoms of water” in an area where current is prevalent, and allowed to remain until fish collect in its shade.

A large rectangular net is suspended at its corners by four ropes, the upper ends of which are held by a man in each catamaran. Moving against the current, the four boats approach the suspended shade rope from downcurrent, with the forward edge of the net held low and the after edge high. When the men in the forward two catamarans feel the net contact the shade rope, they begin to pull it up as quickly as they can, gathering the fish that have collected in its shade.

Although catamarans are still fished in Sri Lanka, I do not know if either of these methods from the Coromandel Coast are still in use.

Sources:
Except where stated otherwise, information and images are from:
James Hornell, Water Transport: Origins and Early Evolution, Cambridge Univ. Press, 1946
James Hornell, Fishing in Many Waters, Cambridge Univ. Press, 1950

Thursday, February 16, 2017

The Yathra Dhoni - A Single-Outrigger Ship of Sri Lanka

yathra dhoni beached
The large vessel is a yathra dhoni. Its outrigger allows it to sit upright on the beach without temporary supports (from Devendra, "The Lost Ships of Lanka.") (Click any image to enlarge)
Seagoing ships with outriggers are a rarity. If one defines “ships” as “(floating mobile nautical) structures which constituted significant elements in the economies of the societies which built and operated them” (Basil Greenhill, in The Earliest Ships: The Evolution of Boats into Ships), then a few of the larger traditional single-outrigger canoes of Oceania would qualify, but based on their size, burthen, and the fact that they are “canoes,” most modern observers would still call them “boats” without hesitation. Some motorized bancas of the Philippines might be (just) large enough to be thought ship-like by some, but no one of these double-outrigger vessels would qualify on the grounds of economic significance.

The yathra dhoni of Sri Lanka and the Coromandel Coast on India, then, may be the only traditional outrigger vessel that was undeniably a “ship.” Large and burthensome enough so as not to be mistaken for a boat, and used as a cargo carrier on both coastal and short oceanic voyages, the single-outrigger yathra dhoni (also spelled yatra dhoni, and also known as the maha-oruwa or maha oru, meaning “big outrigger canoe”) was in use for centuries – possibly thousands of years – and remained in common use into the early twentieth century.

Admiral Paris's drawing of a yathra dhoni
Admiral Paris's drawing of a yathra dhoni (from Essai sur la construction navale des peuples extra-européens ou Collection des navires et pirogues construits par les habitants de l'Asie, de la Malaisie, du Grand Océan et de l'Amérique dessinés et mesurés pendant les voyages autour du monde de "l'Astrolabe", "la Favorite" et "l'Artémise")
Outrigger ships in Sri Lanka were noted by Strabo (65 BCE-19 CE) and Pliny (23-79 CE), and if these were not yathra dhonies per se, they were probably their direct ancestors. A temple carving in Borobudur, Java, dated to the 8th to 10th century CE, shows “the arrival of Aryan emigrants to the Indonesian Islands” (Vitharana) in an outrigger vessel with features similar to the yathra. (The original Aryans, however, were from the area that is now northern India, not Coromandel or Sri Lanka.) Near the end of their history, yathras were known to be trading as far as the Moluccas, so their earlier use transporting Aryans or their neighbors to Java (which, like the Moluccas, is in Indonesia, but closer to India) seems credible.

Most yathras were 50 to 60 feet LOA with a main hull beam of 12 to 15 feet. The largest were 100 feet long with a 20 foot hull beam. Vitharana states that they were 10 to 15 feet in height, although it is unclear what points of measurement are implied. Cargoes ranged from 25 to 75 tonnes, with 50 being typical. The main hull was double-ended, with slack bilges, full midsections, and a slightly hollow entry.

Vosmer's drawing of Dodanduva yathra dhoni model
Tom Vosmer's profile drawing of the Dodanduva yathra dhoni model (from Devendra, "The Lost Ships of Lanka)
The outrigger varied in length, from about a third (Paris) to well over two-thirds (Vosmer’s drawing of a highly detailed model built in the former yathra center of Dodanduva, Sri Lanka, that is widely accepted for its authority) the length of the main hull. It was always mounted on the port side, fastened directly to substantial, downward-curving booms that extended right through the main hull at the level of the deck beams. (One simplified model exists with the outrigger to starboard, but this model lacks a rudder and may represent a different vessel type, or the difference may be due to imprecision on the modeler’s part.) Guys leading diagonally from the main hull to the outer ends of the outrigger booms helped stabilize the outrigger float fore-and-aft.

Dodanduva model of a yathra dhoni
The Dodanduva model of a yathra dhoni (from Green) 
The yathra’s rudder followed the curve of the sternpost. The rudder on the Dodanduva model is enormous and wide, but other reliable sources show rudders of more graceful shape and conventional proportions. From this, it appears that rudders were fitted in a range of sizes and styles. Vitharana refers to a “secondary rudder to act as a leeboard … in the region of the main mast touching the water on the starboard side,” but in no models or drawings that I know of does such a feature appear. A leeboard would appear to be unnecessary, since the hull was built on a keel that provided significant lateral plane to resist leeway. Some models and drawings also show a “gripe” at the bow and a skeg at the stern (upon which the rudder’s lower end was hung), both of which added to the lateral plane and directional stability.

Hornell's sketch of a yathra dhoni
Hornell's sketch of a yathra dhoni
The common rig was a ketch with square headed, loose-footed cloth lugsails and a jib on a bowsprit, said by Green to be “a rig common to the region of the Indian subcontinent.” Some smaller yathras may have had a single mast. Hornell’s sketch of the ketch version shows a second headsail inside the first one, apparently set flying, with its tack led to the port bulwark or possibly to the foredeck. Admiral Paris’s drawing shows a whisker pole holding out the luff of the mainsail. Standing rigging included shrouds, fore- and backstays, and a stay between the mastheads. According to Green, “The arrangement of the halyards was such that they prevent the mizzen yard from passing around the forward side of the mast. It must therefore be concluded that the mizzen sail on the yatra was never tacked, but went aback against the mast when occasionally on a starboard tack.”

Two bulkheads divided the hull into three sections: small bow and stern compartments, the use of which I have not found described, and a large cargo hold between them. Much of the deck was covered by a light, removable deckhouse roofed with split bamboo, leaving only narrow walkways along the sides for the crew to move fore and aft. Sliding cargo hatches were offset to starboard, and a simple cargo handling crane was located to port. In order for this to come in use, lighters – probably small dugout canoes – must have come alongside the main hull between the outrigger booms. But because the vessel would sit upright on a beach, supported by the outrigger, it may be that loading and unloading was often done on land. One assumes that the deckhouse roof was removed before cargo was handled.

The hull of the yathra was of a carvel construction using an unusual combination of stitched and nailed fastening. The planks, a minimum of 2” thick, were stitched to each other with coir rope and nailed to the frames with iron nails and roves. Accounts differ on whether the stitching holes penetrated straight through to the inner surface of the planks or exited on the plank edges. In any case, it is clear that the stitching served only to hold the planks against each other and not to the frames. Details on the order of construction are lacking, but one presumes that the planks were stitched first to make them tight, and nailed second. Joints were caulked with coconut husks and leaves inserted before the stitches were drawn tight.

yathra dhoni construction drawings
Vosmer's construction drawings of the Dodanduva yathra dhoni model (from Devendra, "Pre-Modern Sri Lankan Ships")
Stem and sternpost were fastened to the keel with hooked scarfs held with locking wedges. The frames and deck beams were few in number and widely spaced but of heavy scantlings, providing sufficient overall strength. Deck beams extended through the planking on both sides. Green says the frames were continuous from sheer to sheer, but given their scantlings and the hull’s shape, this seems impossible. Perhaps his information, which is not footnoted, stems from observation of a model which used continuous frames for expediency.

Tom Vosmer took careful measurements of the Dodanduva model, fed the details into a hydrostatics program, and found that the main hull, even without the outrigger, was “reasonably stable.” The outrigger, of course, significantly increased the vessel’s righting moment (by a factor of 100). It also increased drag, and therefore, the ship’s powering requirements. The rig, therefore, could have been smaller and simpler if the (still seaworthy) hull did not have an outrigger attached.

Yathra dhoni at anchor in Kalpitiya, Sri Lanka
Yathra dhoni at anchor in Kalpitiya, Sri Lanka, 1913 (from Devendra, "The Lost Ships of Lanka") 
Yathras were mainly short- and medium-haul cargo vessels, serving ports large and small throughout Sri Lanka and the Coromandel Coast and making regular voyages to the Maldives (550 miles from Colombo, Sri Lanka), although they also sailed at least occasionally to the Moluccas (3,600 miles). Typical cargoes included textiles, rice, salt, fish and fish products, tea, and tiles. A large one carried a crew of 18.

The outrigger was always kept to windward except, perhaps, in the most benign conditions – an unusual and highly limiting practice for a tacking single-outrigger vessel. Working within these limits required coastal voyages to make use of the daily reversal of land and sea breezes: the vessel sailed only during the part of day when the prevailing breeze allowed the outrigger to be kept to windward. On longer voyages, the monsoon breeze dictated direction. This would have meant just a single round trip from Sri Lanka to the Maldives in any given year, whereas a vessel that could sail with either side to windward would be able to make several round trip voyages of that distance each year.

Most accounts tell of the yathra succumbing to competition from steamships around the turn of the twentieth century. Vitharana claims that 40 of them were still serving Dodanduva in the 1930s, but all other accounts tell of the last one being built there to some fanfare in 1930; that is was wrecked on its first voyage in the Maldives; and that that was the end of the tradition.

Sources:
Somasiri Devendra, "Pre-Modern Sri Lankan Ships" in Ships and the Development of Maritime Technology in the Indian Ocean, David Parkin gand Ruth Barnes, editors. Routledge, 2002
Devendra, "The Lost Ships of Lanka," from Maritime Heritage of Lanka: Ancient ports and harbours. National Heritage Trust Sri Lanka, 2013
Devendra, "The Mansion of the Sea," The Island Online - Saturday Magazine
Jeremy Green, "The archaeological contribute to the knowledge of the extra-European shipbuilding at the time of the Medieval and Modern Iberian-Atlantic tradition" Proceedings: International Symposium on Archaeology of Medieval and Modern Ships of Iberian-Atlantic Tradition
James Hornell, Water Transport: Origins and Early Evolution, Cambridge University Press, 1946
The National Trust of Sri Lanka, "The Annapoorani and The Amugoda Oruwa: The Forgotten Ships of Lanka" on Facebook
Corioli Souter, "Travellers and Traders in the Indian Ocean World Curatorial Audio Guide," WAM Audio Tours, Western Austrian Museum
Vini Vitharana, "The ORU & the YATRA" Nautical Archaeological Society, 1992, republished 2012

Wednesday, January 4, 2017

Vatican boat model exhibit, Part 2

In a current temporary exhibit at the Vatican Museums, dozens of models of watercraft from numerous nations and cultures are presented to represent the diversity and interconnectedness of humanity. (See our previous post on this exhibit.) The models are displayed in glass cases (hence the poor quality of the photos that follow) with little explanatory material. 

We present our photos with the scanty information from the exhibit cards in quotation marks, and our own brief observations in parentheses. We invite readers to contribute additional information about any boat in the Comments. Only models representing craft from "outside the Western tradition" are included here. More images of other models from the exhibit will follow in a subsequent post. As always, click any image to enlarge.
"Japan: Sailing boat" (looks like it would be highly capable in surf)
"Indonesia: Sailing boat with outrigger" -- (actually two outriggers. Although the rig is set as a square sail, it appears to be hung asymmetrically on the mast and can probably be canted to form a kind of lugsail.)
"Philippines: Sailing boat with outrigger" -- (again, two outriggers. This is a banca, with a Western-style sailing rig.)
"Sri Lanka: Boat with fisherman" (We wonder if the model attempts to represent any real type of boat, or if it is purely fanciful, its shape dictated by the material available to the modeler. What's surprising and touching about this model is the paddler, who is modeled with a great deal of humanity.)
"India: Pirogue with rowers" (paddlers, actually)
"China: Boat for recreation" (and by that, we mean eating, drinking and sex.)
(background) "India: Pirogue with rowers" (again, paddlers in fact)
"Thailand: Royal boat" (identical exhibit cards for both models)
"China: Sea Junk" (The truncated bow and minimal rig are fascinating aspects of this model, which is certainly not meant to be an accurate representation.)
"Southeast Asia: River boat" (a sampan)
"China: Sea Junk with three masts"
"China: River boat"
"China: Dragon boat for racing"
(Nationality not identified)
Back row:
Left: "Raft for fishing with cormorants"
Center: "Houseboat with passenger and boatmen" (Error in labeling, as this open craft is clearly not a houseboat. The Italian label identifies it as a sampan with a passenger and a boatman)
Right: (label illegible in photo)

Front row: 
Left: "Houseboat with coxswain"
Center: "Houseboat with passenger and boatmen" (Error in labeling, as this open craft is clearly not a houseboat. The Italian label identifies it as a sampan with a passenger and a boatman)
Right: "Houseboat with fisherman"
"Samoa: Seven paddle canoe" (Noticeable similarities to a Samoan canoe in our post about Buckminster Fuller's model collection)