Over time larger vessels were developed that employed a keel on which the planks were sewn. There five major kind of dhows are: 1 the Sambuk , used for pearling, fishing and transporting pilgrims to Mecca; 2 the boom , a vessel built in Bahrain, Oman and Kuwait, and considered the most seaworthy vessel; 3 the baggala , the largest dhow, once used to transport slaves and ivory but rarely seen anymore; 4 the badan , a small craft with a shallow draft; and 5 the ghandaj , a large vessel with a curved stern used on the Arabian Sea for transporting dates, Persian Gulf pearls, timber and smuggled silver.
The boom is a double-ended craft with a hull shape that predates the 16th century. It is believed the designs for these ships originated in Bahrain and spread to place like Oman where they were used for trade with India and Africa. The largest of the traditional Arabian vessels, the boom can carry up to 40 tons and reached lengths of a 40 meters. The key feature of the design is a long straight planked bow-sprit, angled at about 45 degrees.
The sambouk is one of the most graceful and evocative ships. It possesses a low finely tapered bow and a high transom stern. In the past it was the favored pearling vessel. Now it is use mainly for fishing and trading. Large seaworthy dhows have a teak hull with ribs of timber for reinforcement and strength and are held together with cement paste and plugged with cotton strips soaked in fish oil and caulked with whale or shark oil. The preferred wood for the ribs and keel has been teak or a similar wood.
The hand-hewn keel usually have come from a giant log from a single tree. Teak and coconut-palm wood have been favored for masts and spars. Teak has been prized in shipbuilding because it was strong and resistant to sea worms. In the old days It was harvested in forests in India and Southeast Asia. Dhows were sewed together. The timbers were lashed together with ropes made of coconut fibers rolled and twisted by hand. No nails were used.
There was a belief that the oceans floor was a giant magnet that would suck out nails. The art of sewing a ship together remains alive on Agatti Island in Lakshadweep off the southwest coast of India. Coconut ropes are made from the husk sof coconuts rotted in sea water not fresh water , pounded with wooden mallets not iron hammers which weaken the fiber , and spun by hand rope made machines is not strong enough. Some ships had metal fasteners. Metal is more durable than coconut rope and was better on fighting ships for securing guns.
Showers consisted seawater drawn with a bucket and dumped over oneself. The triangular lateen sails on dhows have traditionally been made from woven palm leaves, coconut fiber, reeds or cotton. Vessels with lateen sails are faster and more maneuverable than than ships with square-rigged sails. Lateen sails copied from dhows were used on European explorer ships.
Large dhows include a keelson, a reinforcing timber fastened directly to the top of the keel to hold the edges of the garboards the planks next to keel in place. Dhows are made using the shell-building method in which vessels are created one plank at a time. Modifications can be made in the middle of construction by altering the shape of the planks or the angles of attachment.
Why is the lateen sail important? The lateen sail was crucial for the development of ships that were maneuverable and reliable under sail power alone. These improvements made it possible for ships to increase in size, giving them the ability to carry cargo more profitably and more reliably.
They also made ships more important as weapons of war. Honorat Castroman Pundit. How do you pronounce dhow? Here are 4 tips that should help you perfect your pronunciation of 'dhow':.
Break 'dhow' down into sounds: [DOW] - say it out loud and exaggerate the sounds until you can consistently produce them. Record yourself saying 'dhow' in full sentences, then watch yourself and listen. Jhony Jess Pundit. What does a Chinese junk look like?
Junk , classic Chinese sailing vessel of ancient unknown origin, still in wide use. High-sterned, with projecting bow, the junk carries up to five masts on which are set square sails consisting of panels of linen or matting flattened by bamboo strips. Each sail can be spread or closed at a pull, like a venetian blind.
Chiquinquira Hackert Pundit. How did Lateen Sails improve navigation? Lateen sail , triangular sail that was of decisive importance to medieval navigation. The sail , its free corner secured near the stern, was capable of taking the wind on either side, and, by enabling the vessel to tack into the wind, the lateen immensely increased the potential of the sailing ship.
Lateen sail. What type of sail did dhows have? When the Monsoon winds carried trade across the Indian Ocean, the vessel of choice was the Dhow , with its characteristic lateen sail made with traditional Merikani cloth.
Ask A Question. Co-authors: The dhow was known for two distinctive features. Stitched boats were made by sewing the hull boards together with fibers, cords or thongs. The idea of a boat made up of planks sewn together seems strange. Actually, it is a type that has been in wide use in many parts of the world and in some places still is.
In the Indian Ocean, it dominated the waters right up to the fifteenth century, when the arrival of the Portuguese opened the area to European methods. A Greek sea captain or merchant who wrote in the first century AD reports the use of small sewn boats off Zanzibar and off the southern coast of Arabia.
Marco Polo saw sewn boats at Hormuz at the entrance to the Persian Gulf. It keeps well and is not corroded by sea-water but it will not stand well in a storm. Yule, 3rd edition, London, , I, p. They were surely right in connecting sewn boats with an early age. They were wrong only in assuming that it had not lived on: marine archeologists have found remains of sewn boats that date from the sixth century BC on into the Roman Imperial age.
By the fashioning of a hull by sewing planks together, despite its early appearance and continued existence, remained a byway. As the following chapters will reveal, the mainstream of boat building followed a different channel.
According to Hourani, fully stitched construction was observed by medieval writers in the Red Sea, along the east African coast, in Oman, along the Malabar and Coromandel Coasts of India and in the Maldives and Laccadive Islands.
Deloche summarizes the characteristics of pre-European influence, ocean going Indian ships based on pictorial evidence. They were double-ended craft. Prior to the eleventh century AD, the stern was raked, but after that time, a long projecting bow became the predominate characteristic.
Hull planks were flush-laid and stitched with the stitches crossed and penetrating right through the planks. A possible reconstruction of early ocean-going dhows. Their main characteristics were sewn double ended construction, steering oars at the stern and a lateen rigged sail.
Contemporary records prove without a doubt that during the third millennium BC, Babylon carried on extensive overseas trade through the Persian Gulf southward to the east African coast and eastward to India. Hardly anything is known about the vessels used on these ambitious runs other than that they were very small; the largest mentioned has a capacity of some 28 tons.
For the size of the gur, see Appendix 1, note 5. In early times the masts and yards were probably made of coconut wood and teak, although a number of woods were used in later construction. It is thought that originally sails were woven from coconut of palm leaves, and that eventually cotton cloth became the favorite for merchants on long voyages. Cotton cloth was manufactured in India. Two main sails were carried, one for night and bad weather, and the other for day and fair weather.
Sails on a dhow could not be reefed. The lateen sail used by Arabs stops short of being completely triangular. Their sails retained a luff at the fore part in proportion to the leech of roughly in the mainsail. The retention of this luff added a much greater area of sail to be hoisted than would a completely triangular design. During the Byzantine era the Lateen sail completed its evolution into a triangle, and this idea spread from Byzantium to the rest of Europe, where it developed into the varieties of mizzen sails which later gave European sailing ships so much flexibility.
From there it was eventually developed in the west into all the types of fore-and-aft rig known to yachtsmen today, a form superior still to the lateen for sailing close to the wind. It is assumed by some that the lateen sail developed on the Red Sea, and spread from there to the Mediterranean Sea and Persian Gulf.
There is some evidence that a fore-and-aft lateen rig arrived in the Aegean Sea from the 2nd century onward, and in the Persian Gulf around this time. The masts and rigging of the dhow was similar in all types of dhows, with added rigging in larger vessels. Masts were secured at the base by being slotted into a mast step, which fit over the floor timbers. The rigging of a typical dhow can be seen in the diagram below. Cables were often made of coir.
The lateen sail on the dhow looks triangular to the casual observer, but in fact it is quadrilateral and is correctly termed a settee sail. Was sail is made of several cloths, sewn parallel to luff and leech.
Different types of sail were made according to the requirements: a sail wanted for reaching would be made less flat and with a fuller luff than a sail wanted for beating.
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