Junk (ship)

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A junk is a Chinese sailing vessel. The English name comes from Malay dgong or jong. Junks were originally developed during the Han Dynasty (220 BCE-200 CE) and further evolved to represent one of the most successful ship types in history.

Contents

Design

Junks are efficient and sturdy ships that were traveling across oceans as early as the 2nd century AD. They incorporated numerous technical advances in sail plan and hull designs that were later adopted in Western shipbuilding.

The historian H. Warington Smith considered the junk as one of the most efficient of ship designs:

"As an engine for carrying man and his commerce upon the high and stormy seas as well as on the vast inland waterways, it is doubtful if any class of vessel is more suited or better adapted to its purpose than the Chinese junk, and it is certain that for flatness of sail and handiness, the Chinese rig is unsurpassed." (H. Warington Smith)

Sail plan

The structure and flexibility of the sails make the junk easy to sail, and fast since the sails are not square rigged, i.e. they can be angled when sailing upwind.

The sails are cut elliptically and slightly curved with bamboo inserts (battens), giving them the shape of an airfoil, and permitting them to sail well on any point of sail. The sails can also be easily reefed and adjusted for fullness, to accommodate various wind strengths. The battens also give the sails added strength, and make them more resistant than traditional sails to holing or rot. Junk sails have much in common with the most aerodynamically efficient sails used today in windsurfers or catamarans, although their design can be traced back as early the 3rd century AD.

The rigging is very simple because bamboo is very strong; thus fewer ropes are needed.

The sail-plan is also spread out between multiple masts, allowing for a powerful sail surface, and a good repartition of efforts, an innovation adopted in the West around 1304. The rig is fore-and-aft, allowing for good sailing into the wind.

Hull design

Classic junks were built of softwoods – though in Guangdong in teak with multiple compartments accessed by separate hatches and ladders: similar in structure to the interior stem of bamboo. These were not watertight, as is commonly believed, all wrecks so far recovered having limber holes at the base of each bulkhead. The largest junks were built for world exploration in the 1400s, and were around 120 meters in length. (See Zheng He)

Rudders

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Junks employed stern-mounted rudders centuries before their adoption in the West, though in fact the rudder origin, form and construction was completely different from that adopted in the West. It was an innovation which permitted the steering of large, high-freeboard ships, though the system of mounting was chronically weak and required large numbers of crew to control in strong weather. The world's oldest known depiction of a stern-mounted rudder can be seen on a pottery model of a junk dating from the 1st Century, though some scholars think this may be a steering oar - a possible interpretation given that the model is of a river boat that was probably towed or poled. By contrast, the West's oldest known stern-mounted rudder can be found on church carvings dating to around 1180.

Also, from sometime in the 13th-15th centuries many junks incorporated "fenestrated rudders" (rudder with holes in them), an innovation adopted in the West in 1901 to decrease the vulnerability of torpedo boats rudders when manoeuvering at high speed. Likewise the Chinese discovery - which probably came about through fortuitous weaknesses in knotted pine - was probably adopted because the reduced stresses helped cope with the weak and vulnerable mountings of junk rudders.

Separate compartments

Another characteristic of junks, interior compartments, allowed reinforced the ship structure and reduced the rapidity of flooding in case of holing. The compartments were not watertight, as popular belief has it. All wrecks discovered so far have limber holes, probably for the sensible reason that with early Chinese pump technology and heavy tropical rains, multiple watertight compartments would have been impractical. This innovation was misunderstood in the West in the late 18th century and was not adopted at that time. Later in the 19th century a similar system, but beginning with longitudinal bulkheads, was adopted to strengthen early iron ships to counter hogging and sagging.

Benjamin Franklin wrote in a 1787 letter on the project of mail packets between the United States and France:

"As these vessels are not to be laden with goods, their holds may without inconvenience be divided into separate apartments, after the Chinese manner, and each of these apartments caulked tight so as to keep out water" (Benjamin Franklin, 1787).

In 1795, Sir Samuel Bentham, inspector of dockyards of the Royal Navy, and designer of six new sailing ships, argued for the adoption of "partitions contributing to strength, and securing the ship against foundering, as practiced by the Chinese of the present day". His idea was not adopted. Bentham had been in China in 1782, and he acknowledged that he had got the idea of watertight compartments by looking (obviously not too closely) at Chinese junks there. Bentham was a friend of Isambard Brunel, so it is possible that he had some influence on Brunel's adoption of longitudinal, strengthening bulkheads in the lower deck of the SS Great Britain.

Leeboards & centerboards

Leeboards and centerboards, used to stabilize the junk and to improve its capability to sail upwind are documented from a 759 AD book by Li Chuan, an innovation adopted by Portuguese and Dutch ships around 1570.

Other innovations included the square-pallet bilge pump, which were adopted by the West during the 16th century. Junks also relied on the compass for navigational purposes.

History

Junks were originally developed during the Han Dynasty (220 BC-200 AD).

2nd century junks (Han Dynasty)

The 3rd century book "Strange Things of the South" (南州異物志) by Wan Chen (萬震) describes junks capable of carrying 700 people together with 260 tons of cargo ("more than 10,000 "斛"). He explains the ship's design as follows:

"The four sails do not face directly forward, but are set obliquely, and so arranged that they can all be fixed in the same direction, to receive the wind and to spill it. Those sails which are behind the most windward one receiving the pressure of the wind, throw it from one to the other, so that they all profit from its force. If it is violent, (the sailors) diminish or augment the surface of the sails according to the conditions. This oblique rig, which permits the sails to receive from one another the breath of the wind, obviates the anxiety attendant upon having high masts. Thus these ships sail without avoiding strong winds and dashing waves, by the aid of which they can make great speed" ("Strange Things of the South", Wan Chen, from Robert Temple).

Image:SongJunk.jpg A 260 AD book by Kang Tai (康泰) also described ships with seven masts, traveling as far as Syria.

10th-13th century junks (Song Dynasty)

The great trading dynasty of the Song employed junks extensively. The naval strength of the Song, both mercantile and military, became the backbone of the naval power of the following Yuan dynasty. Particular the Mongol invasions of Japan (1274-1284), as well as the Mongol invasion of Java essentially relied on recently acquired Song naval capabilities. The ship to the right's dimensions are 360'x 110'x 120'.

14th century junks (Yuan Dynasty)

The enormous characteristics of the Chinese ships of the Medieval period is described in Chinese sources, and is confirmed by Western travelers to the East, such as Marco Polo, Ibn Battuta and Niccolo Da Conti. According to Ibn Battuta, who visited China in 1347:

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... We stopped in the port of Calicut, in which there were at the time thirteen Chinese vessels, and disembarked. On the China Sea traveling is done in Chinese ships only, so we shall describe their arrangements. The Chinese vessels are of three kinds; large ships called chunks (junks), middle sized ones called zaws (dhows) and the small ones kakams. The large ships have anything from twelve down to three sails, which are made of bamboo rods plaited into mats. They are never lowered, but turned according to the direction of the wind; at anchor they are left floating in the wind.
A ship carries a complement of a thousand men, six hundred of whom are sailors and four hundred men-at-arms, including archers, men with shields and crossbows, who throw naphtha. Three smaller ones, the "half", the "third" and the "quarter", accompany each large vessel. These vessels are built in the towns of Zaytun (a.k.a Zaitun; today's Quanzhou; 刺桐) and Sin-Kalan. The vessel has four decks and contains rooms, cabins, and saloons for merchants; a cabin has chambers and a lavatory, and can be locked by its occupants.

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This is the manner after which they are made; two (parallel) walls of very thick wooden (planking) are raised and across the space between them are placed very thick planks (the bulkheads) secured longitudinally and transversely by means of large nails, each three ells in length. When these walls have thus been built the lower deck is fitted in and the ship is launched before the upper works are finished. (Ibn Battuta).

Niccolo Da Conti in his relations of his travels in Asia between 1419 and 1444, matter-of-factly describes huge junks of about 2,000 tons, more than four times the size of 16th century Western galleons:

They make ships larger than ours, about 2,000 tons in size, with five sails and as many masts. The lower part is made of three decks, so as to better resist storms, which occur frequently. These ships are separated into several compartments, so that if one is touched during a storm, the others remain intact." (Niccolo Da Conti)

15th-17th century junks (Ming Dynasty)

Expedition of Zheng He

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The largest junks ever built were probably those of Admiral Zheng He, for his expeditions in the Indian Ocean. According to Chinese sources, the fleet comprised 30,000 men and over 300 ships at its height.

The 1405 expedition consisted of 27,000 men and 317 ships, composed of:

  • "Treasure ships", used by the commander of the fleet and his deputies (Nine-masted junks, about 400 feet long and 160 feet wide).
  • "Horse ships", carrying tribute goods and repair material for the fleet(Eight-masted junks, about 339 feet long and 138 feet wide)
  • "Supply ships", containing food-staple for the crew (Seven-masted junks, about 257 feet long and 115 feet wide).
  • "Troop transports" (Six-masted junks, about 220 feet long and 83 feet wide).
  • "Fuchuan warships" (Five-masted junks, about 165 feet long).
  • "Patrol boats" (Eight-oared, about 120 feet long).
  • "Water tankers", with 1 month supply of fresh water and sustainability.

Asian trade

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Chinese junks were used extensively in Asian trade during the 16th and 17th century, especially to Japan, where they competed with Japanese Red Seal Ships, Portuguese carracks and Dutch galleons, and to Southeast Asia. Richard Cocks, the head of the English trading factory in Hirado, Japan, recorded that 50 to 60 Chinese junks visited Nagasaki in 1612 alone.

These junks were usually three masted, and averaging between 200 and 800 tons in size, the largest ones having around 130 sailors, 130 traders and a sometimes hundreds of passengers.

Expulsion of the Dutch from Taiwan

In 1661, a naval fleet of 400 junks and 25.000 men led by the Ming loyalist Zheng Chenggong (Cheng Ch'eng-kung in Wade-Giles, known in the West as Koxinga), arrived in Taiwan to oust the Dutch from Zeelandia. Following a nine month siege, Cheng captured the Dutch fortress Fort Zeelandia. A peace treaty between Koxinga and the Dutch Government was signed at Castle Zeelandia on February 1st 1662, and Taiwan became Koxinga's base for the Kingdom of Tungning.

19th century junks (Qing Dynasty)

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Junks remained considerable in size and played a key role in Asian trade until the 19th century. One of these junks, Keying, sailed from China around the Cape of Good Hope to the United States and England between 1846 and 1848. She testifies to the power of Chinese shipping and shipbuilding at the time of the beginning of industrialization in the West.

The Keying was praised by the English as excellent in sea-worthiness, and practically superior to their own:

"She proved herself an excellent sea-boat; and her powers of weathering a storm equal, if not surpass, those of vessels of British build." (Illustrated London News, 1848)

She was also fast, sailing between Boston and England in 21 days:

"The Keying next visited Boston, whence she sailed direct for London on the 17th of February last, and arrived in St Aubin's Bay, Jersey, on the 15th March, having performed the voyage, from land to land, in 21 days - a short period even for the American packet-ships." (Illustrated London News, 1848)

See also

References

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