Chinese treasure ship

A Chinese treasure ship (, literally "gem ship") is a type of large wooden ship in the fleet of admiral Zheng He, who led seven voyages during the early 15th-century Ming dynasty. The size of the treasure ships, the largest ships in Zheng He's fleet, has been a subject of much controversy, with some old Chinese records mentioning the size of 44 zhang or 44.4 zhang, which has been interpreted by some modern scholars as over 100 m in length, while others have stated that Zheng He's largest ship was around 70 m or less.

Chinese


According to the  (1658), the first voyage consisted of 63 treasure ships crewed by 27,870 men.

The History of Ming (1739) credits the first voyage with 62 treasure ships crewed by 27,800 men. A Zheng He era inscription in the Jinghai Temple in Nanjing gave the size of Zheng He ships in 1405 as 2,000 liao (500 tons), but did not give the number of ships.

Alongside the treasures were also another 255 ships according to the  (1520), giving the combined fleet of the first voyage a total of 317 ships. However, the addition of 255 ships is a case of double accounting according to Edward L. Dreyer, who notes that the Taizong Shilu does not distinguish the order of 250 ships from the treasure ships. As such the first fleet would have been around 250 ships including the treasure ships.

The second voyage consisted of 249 ships. The Jinghai Temple inscription gave the ship dimensions in 1409 as 1500 liao (375 tons).

According to the Xingcha Shenglan (1436), the third voyage consisted of 48 treasure ships, not including other ships.

The Xingcha Shenglan states that the fourth voyage consisted of 63 treasure ships crewed by 27,670 men.

There are no sources for number of ships or men for the fifth and sixth voyages.

According to the Liujiagang and Changle Inscriptions, the seventh voyage had "more than a hundred large ships".

Yemen
The most contemporary non-Chinese record of the expeditions is an untitled and anonymous annalistic account of the then-ruling Rasūlid dynasty of Yemen, compiled in the years 1439–1440. It reports the arrival of Chinese ships in 1419, 1423, and 1432, which approximately correspond to Zheng He's fifth, sixth, and seventh voyages. The 1419 arrival is described thus:

The later Yemeni historian, Ibn al-Daybaʿ (1461–1537), writes:

Mamluks
Mamluk historian Ibn Taghribirdi (1411–1470) writes:

Niccolò de' Conti
Niccolò de' Conti (c. 1395–1469), a contemporary of Zheng He, was also an eyewitness of Chinese ships in Southeast Asia, claiming to have seen five-masted junks of about 2000 tons* burthen:


 * Other translations of the passage give the size as a 2000 butts, which would be around 1000 tons, a butt being half a ton. Christopher Wake noted that the transcription of the unit is actually vegetes, that is Venetian butt, and estimated a burthen of 1300 tons.

Song and Yuan junks
Although active prior to the treasure voyages, both Marco Polo (1254–1325) and Ibn Battuta (1304–1369) attest to large multi-masted ships carrying 500 to 1000 passengers in Chinese waters. The large ships (up to 5,000 liao or 1520–1860 tons burden) would carry 500–600 men, and the second class (1,000–2,000 liao) would carry 200–300 men. Unlike Ming treasure ships, Song and Yuan great junks were propelled by oars, and had with them smaller junks, probably for help in maneuvering. The largest junks (5,000 liao) may have had a hull length twice that of a Quanzhou ship (1,000 liao), Liuhe, Taicang is 68 m. However, the usual Chinese trading junks pre-1500 was around 20 - 30 m long, with the length of 30 m only becoming the norm after 1500 CE. Large size could be a disadvantage for shallow harbors of southern seas, and the presence of numerous reefs exacerbates this.

Taizong Shilu
The most contemporary accounts of the treasure ships come from the Taizong Shilu, which contains 24 notices from 1403 to 1419 for the construction of ships at several locations.

On 4 September 1403, 200 "seagoing transport ships" were ordered from the Capital Guards in Nanjing.

On 1 March 1404, 50 "seagoing ships" were ordered from the Capital Guards.

In 1407, 249 vessels were ordered "to be prepared for embassies to the several countries of the Western Ocean".

On 14 February 1408, 48 treasure ships were ordered from the Ministry of Works in Nanjing. This is the only contemporary account containing references to both treasure ships and a specific place of construction. Coincidentally, the only physical evidence of treasure ships comes from Nanjing.

On 2 October 1419, 41 treasure ships were ordered without disclosing the specific builders involved.

Longjiang Chuanchang Zhi
's Longjiang Chuanchang Zhi (1553), also known as the Record of the Dragon River Shipyard, notes that the plans for the treasure ships had vanished from the ship yard in which they were built.

Sanbao Taijian Xia Xiyang Ji Tongsu Yanyi
According to 's 1597 novel Sanbao Taijian Xia Xiyang Ji Tongsu Yanyi (Eunuch Sanbao Western Records Popular Romance), the treasure fleet consisted of five distinct classes of ships:


 * Treasure ships (宝船, Bǎo Chuán) nine-masted, 44.4 by 18 zhang, about 127 m long and 52 m wide.
 * Equine ships (馬船, Mǎ Chuán), carrying horses and tribute goods and repair material for the fleet, eight-masted, 37 by 15 zhang, about 103 m long and 42 m wide.
 * Supply ships (粮船, Liáng Chuán), containing staple for the crew, seven-masted, 28 by 12 zhang, about 78 m long and 35 m wide.
 * Transport ships (坐船, Zuò Chuán), six-masted, 24 by 9.4 zhang, about 67 m long and 25 m wide.
 * Warships (战船, Zhàn Chuán), five-masted, 18 by 6.8 zhang, about 50 m long.

Edward L. Dreyer claims that Luo Maodeng's novel is unsuitable as historical evidence. The novel contains a number of fantasy elements; for example the ships were "constructed with divine help by the immortal Lu Ban". Scholars have worked, however, to distinguish the fictional elements from those that the author had access to but have subsequently been lost, including both written and oral sources.

Contemporary descriptions
The contemporary inscription of Zheng He's ships in the Jinghai temple (靜海寺—Jìng hǎi sì) inscription in Nanjing gives sizes of 2,000 liao (500 tons) and 1,500 liao (275 tons), which are far too low than would be implied by a ship of 444 chi (450 ft) given by the History of Ming. In addition, in the contemporary account of Zheng He's 7th voyage by Gong Zhen, says it took 200 to 300 men to handle one of Zheng He's ships. Ming minister Song Li indicated a ratio of 1 man per 2.5 tons of cargo, which would imply Zheng He's ships were 500 to 750 tons.

The inscription on the tomb of Hong Bao, an official in Zheng He's fleet, mentions the construction of a 5,000 liao displacement ship.

5,000 liao ship
In June 2010, a new inscription was found in Hong Bao's tomb, confirming the existence of the Ming dynasty's 5,000 liao ship. According to a resident of Hangzhou in 1274, large merchant ships of 5,000 liao could accommodate between 500 to 600 passengers while ships of 1,000 to 2,000 liao could carry 200 to 300 passengers. Taking the liao to be 500 lb burthen, that would be 1,250 tons burthen. Sleeswyk argued that the term liao refers to the displacement and not cargo weight, one liao would be equivalent to 500 kg of displacement. According to Zheng Ming, the 5,000 liao ship would have a dimension of 71.1 m, width of 14.05 m, with 6.1 m draught, and the displacement would reach more than 2,700 tons. The 5,000 liao ship may have been used as the flagship but the number of ships was relatively small. Wake argued that the 5,000 liao ships were not used until after the 3rd voyage, when the voyages were extended beyond India. Judging from the three images from the Ming era, the largest ships had 3–4 main masts and 2–3 auxiliary masts.

History of Ming
According to the History of Ming (Ming shi—明史), completed in 1739, the treasure ships were 44 zhang, 4 chi, i.e. 444 chi in length, and had a beam of 18 zhang. The dimensions of ships are no coincidence. The number "4" has numerological significance as a symbol of the 4 cardinal directions, 4 seasons, and 4 virtues. The number 4 was an auspicious association for treasure ships. These dimensions first appeared in a novel published in 1597, more than a century and a half after Zheng He's voyages. The 3 contemporary accounts of Zheng He's voyages do not have the ship dimensions.

The zhang was fixed at 141 inches in the 19th century, making the chi 14.1 inches. However the common Ming value for chi was 12.2 inches and the value fluctuated depending on region. The Ministry of Works used a chi of 12.1 inches while the Jiangsu builders used a chi of 13.3 inches. Some of the ships in the treasure fleet, but not the treasure ships, were built in Fujian, where the chi was 10.4 to 11 inches. Assuming a range of 10.5 to 12 inches for each chi, the dimensions of the treasure ships as recorded by the History of Ming would have been between 385 by 157.5 feet and 440 by 180 feet (117.5 by 48 metres, and 134 by 55 metres). Louise Levathes estimates that it had a maximum size of 110–124 m (390–408 feet) long and 49–51 m (160–166 feet) wide instead, taking 1 chi as 10.53–11.037 inches.

According to British scientist, historian and sinologist Joseph Needham, the dimensions of the largest of these ships were 135 metres by 55 metres. American historian Edward L. Dreyer is in broad agreement with Needham's views.

Modern estimates
Modern scholars have argued on engineering grounds that it is highly unlikely that Zheng He's ship was 450 ft in length. Guan Jincheng (1947) proposed a much more modest size of 20 zhang long by 2.4 zhang wide (204 ft by 25.5 ft or 62.2 m by 7.8 m). Xin Yuan'ou, a shipbuilding engineer and professor of the history of science at Shanghai Jiao Tong University, argues that Zheng He's treasure ships could not have been 450 ft long, and suggests that they were probably closer to 200–250 ft (61–76 m) in length. Hsu Yun-Ts'iao does not agree with Xin Yuan'ou: Estimating the size of a 2,000 liao ship with the Treatise of the Longjiang shipyard (龙江船厂志—lóng jiāng chuánchǎng zhì) at Nanjing, the size is as follows: LOA 166 ft, bottom's hull length 102.6 ft, overhanging "tail" length 23.4 ft, front depth 6.9 ft, front width 19.5 ft, mid-hull depth 8.1 ft, mid-hull width 24.3 ft, tail depth 12 ft, tail width 21.6 ft, and the length to width ratio is 7:1. Arabic Studies and Islamic Material Culture researcher Dionisius A. Agius estimated a size of 200–250 ft (60.96 m–76.2 m) and maximum weight of 700 tons for the escort ships based on his observation of Arabic and Asian shipwrights, while for the flag ship, Agius estimates 447 ft (139.4 m) at very most, based on the with information about the ship's weight in literature and possible dimensions of the 15th century technologies. Tang Zhiba, Xin Yuan'ou, and Zheng Ming have calculated the dimensions of the 2,000 liao ship, obtaining a length of 61.2 m, width of 13.8 m, and draught of 3.9 m. Zheng Ming believes that the "Heavenly Princess Classics" depict 2,000 liao ships.



André Wegener Sleeswyk extrapolated the size of liao (料 — material) by deducing the data from mid-16th century Chinese river junks. He suggested that the 2,000 liao ships were bao chuan (treasure ship), while the 1,500 liao ships were ma chuan (horse ship). In his calculations, the treasure ships would have had a length of 52.5 m, a width of 9.89 m, and a height of 4.71 m. The horse ships would have a length of 46.63 m, a width of 8.8 m, and a height of 4.19 m. Richard Barker estimated that the treasure ships would have a length of 230 ft, a width of 65 ft, and a draught of 20 ft. He estimated it using an assumed displacement of 3100 tons.



Naval engineer and historian Xin Yuan'ou has argued that Zheng He's ships could not have been as large as recorded in the History of Ming for the following reasons:


 * 1) Ships of the dimensions given in the Ming shi would have been 15,000–20,000 tons according to his calculations, exceeding a natural limit to the size of a wooden ocean-going ship of about 7,000 tons displacement.
 * 2) With the benefit of modern technology it would be difficult to manufacture a wooden ship of 10,000 tons, let alone one that was 1.5 to 2 times that size. It was only when ships began to be built of iron in the 1860s that they could exceed 10,000 tons.
 * 3) Watertight compartments characteristic of traditional Chinese ships tended to make the vessels transversely strong but longitudinally weak.
 * 4) A ship of these dimensions would need masts that were 100 meters (328 feet) tall. Several timbers would have to be joined vertically. As a single tree trunk would not be large enough in diameter to support such a mast, multiple timbers would need to be combined at the base as well. There is no evidence that China had the type of joining materials necessary to accomplish these tasks.
 * 5) A ship with 9 masts would be unable to resist the combined strength and force of such huge sails; she would not be able to cope with strong wind and would break.
 * 6) It took four centuries (from the Renaissance to the modern era) for Western ships to increase in size from 1500 to 5000 tons displacement. For Chinese ships to have reached three or four times this size in just two years (from Emperor Yongle's accession in 1403 to the launch of the first expedition in 1405) was unlikely.
 * 7) The 200 to 300 sailors as mentioned by Gong Zhen could not have managed a 20,000 ton ship. According to Xin, a ship of such size would have had to have a complement of 8,000 men.

From the comments of modern scholars on Medieval Chinese accounts and reports, it is apparent that a wooden ship had a natural limit to her size, which going beyond would have made her structurally unsafe as well as causing a considerable loss of maneuverability, something the Spanish Armada ships famously experienced. Beyond a certain size (about 300 feet or 91.44 m in length) a wooden ship is structurally unsafe. It was not until the mid to late 19th century that the length of the largest western wooden ship began to exceed 100 meters, even this was done using modern industrial tools and iron parts.

One suggestion for the 44 zhang size treasure ships, if they were built, was that they were used only for a display of imperial power by the emperor and imperial bureaucrats on the Yangtze River when on court business, including when reviewing Zheng He's actual expedition fleet. The Yangtze River, with its calmer waters, may have been navigable for such large but unseaworthy ships. Zheng He would not have had the privilege in rank to command the largest of these ships. Some of the largest ships of Zheng He's fleet were the 6 masted 2000-liao ships. This would give burthen of 500 tons and a displacement tonnage of about 800 tons. Because they were built and based in Nanjing, and repeatedly sailed along the Yangtze river (including in winter, when the water is low), their draught cannot exceed 7–7.5 m. It is also known that Zheng He's fleet visited Palembang in Sumatra, where they needed to cross the Musi river. It is unknown whether Zheng He's ships sailed as far as Palembang, or whether they waited on the shore in the Bangka Strait while the smaller ships sailed at Musi; but at least the draught of the ship that reached Palembang could not have been more than 6 m.

Measurement conversion
It is also possible that the measure of zhang (丈) used in the conversions was mistaken. Seventeenth-century Ming records state that the European East Indiamen and galleons were 30, 40, 50, and 60 zhang (90, 120, 150, and 180 meters) in length. The length of a Dutch ship recorded in the History of Ming was 30 zhang. If the zhang is taken to be 3.2 meters, the Dutch ship would be 96 m or 316 ft long, an enormous increase over the largest Dutch ships of the time. The Dutch Hongyi cannon was recorded to be more than 2 zhang (6.4 m or 21 ft) long. A comparative study by Hu Xiaowei (2018) concluded that 1 zhang would be equal to between 1.5 meters and 1.6 meters; this means the Dutch ship would be 45–48 m (147–157 ft) long and the cannon would be 3–3.2 m (9.8–10.5 ft) long. Taking the upper limit of 1.6 meters for 1 zhang, Zheng He's 44 zhang treasure ship would be 70.4 m long and 28.8 m wide, or 22 zhang long and 9 zhang wide if the zhang is taken to be 3.2 m. It is known that the measuring unit during the Ming era was not unified: A measurement of East and West Pagoda in Quanzhou resulted in a zhang unit of 2.5–2.56 m. According to Chen Cunren, one zhang in the Ming Dynasty is only half a zhang in modern times.

Structure
The keel consisted of wooden beams bound together with iron hoops. In stormy weather, holes in the prow would partially fill with water when the ship pitched forward, thus lessening the violent turbulence caused by waves. Treasure ships also used floating anchors cast off the sides of the ship in order to increase stability. The stern had two 2.5 m (8 foot) iron anchors weighing over a thousand pounds each, used for mooring offshore. Like many Chinese anchors, these had four flukes set at a sharp angle against the main shaft. Watertight compartments were also used to add strength to the treasure ships. The ships also had a balanced rudder which could be raised and lowered, creating additional stability like an extra keel. The balanced rudder placed as much of the rudder forward of the stern post as behind it, making such large ships easier to steer. Unlike a typical fuchuan warship, the treasure ships had nine staggered masts and twelve square sails, increasing its speed. Treasure ships also had 24 cast-bronze cannons with a maximum range of 240 to 275 m (800–900 feet). However, treasure ships were considered luxury ships rather than warships. As such, they lacked the fuchuan's raised platforms or extended planks used for battle.

Non-gunpowder weapons on Zheng He's vessels seems to be bows. For gunpowder weapons, they carried bombards (albeit shorter than Portuguese bombards) and various kind of hand cannons, such as can be found on early 15th century Bakau shipwreck. Comparing with Penglai wrecks, the fleet may have carried cannons with bowl-shaped muzzle (which dates back to late Yuan dynasty), and iron cannons with several rings on their muzzle (in the wrecks they are 76 and 73 cm long, weighing 110 and 74 kg), which according to Tang Zhiba, a typical of early Ming iron cannon. They may also carry incendiary bombs (quicklime bottles). Girolamo Sernigi (1499) gives an account of the armament of what are possibly the Chinese vessels: "It is now about 80 years since there arrived in this city of Chalicut certain vessels of white Christians, who wore their hair long like Germans, and had no beards except around the mouth, such as are worn at Constantinople by cavaliers and courtiers. They landed, wearing a cuirass, helmet, and visor, and carrying a certain weapon [sword] attached to a spear. Their vessels are armed with bombards, shorter than those in use with us. Once every two years they return with 20 or 25 vessels. They are unable to tell what people they are, nor what merchandise they bring to this city, save that it includes very fine linen-cloth and brass-ware. They load spices. Their vessels have four masts like those of Spain. If they were Germans it seems to me that we should have had some notice about them; possibly they may be Russians if they have a port there. On the arrival of the captain we may learn who these people are, for the Italian-speaking pilot, who was given him by the Moorish king, and whom he took away contrary to his inclinations, is with him, and may be able to tell. — Girolamo Sernigi (1499) about the then-unknown Chinese visitors"

Physical evidence


From 2003 to 2004, the Treasure Shipyard was excavated in northwestern Nanjing (the former capital of the Ming Dynasty), near the Yangtze River. Despite the site being referred to as the "Longjiang Treasure Shipyard" (龍江寶船廠—lóng jiāng bǎo chuánchǎng) in the official names, the site is distinct from the actual Longjiang Shipyard, which was located on a different site and produced different types of ships. The Treasure Shipyard, where Zheng He's fleet were believed to have been built in the Ming Dynasty, once consisted of thirteen basins (based on a 1944 map), most of which have now been covered by the construction of buildings in the 20th century. The basins are believed to have been connected to the Yangtze via a series of gates. Three long basins survive, each with wooden structures inside them that were interpreted to be frames for the ships to be built on. The largest basin extends for a length of 421 m. While they were long enough to accommodate the largest claimed Zheng He treasure ship, they were not wide enough to fit even a ship half the claimed size. The basin was only 41 m wide at most, with only a 10 m width area of it showing evidence of structures. They were also not deep enough, being only 4 m deep. Other remains of ships in the site indicate that the ships were only slightly larger than the frames that supported them. Moreover, the basin structures were grouped into clusters with large gaps between them, if each cluster was interpreted as a ship framework, then the largest ship would not exceed 75 m at most, probably less.

In 1957, a large 11-meter-long rudder shaft was discovered during excavations at the Treasure shipyards. The rudder blade, which did not survive, was attached to a 6-meter section of the axis. According to Chinese archaeologists, the area of the rudder was approximately 42.5 m², and the length of the ship to which it belonged was estimated at 149–166 meters. However, such use of this piece of archeological evidence rests upon supposing proportions between the rudder and the length of the ship, which have also been the object of intense contestation: That length was estimated using steel, engine-driven ship as the reference. By comparing the rudder shaft to the Quanzhou ship, Church estimated that the ship was 150 ft long.

Speed
The treasure ships were different in size, but not in speed. Under favorable conditions, such as sailing with the winter monsoon from Fujian to Southeast Asia, Zheng He's fleet developed an average speed of about 2.5 kn; on many other segments of his route, a significantly lower average speed was recorded, of the order of 1.4 - 1.8 kn.

As historians note, these speeds were relatively low by the standards of later European sailing fleets, even in comparison with ships of the line, which were built with an emphasis on armament rather than speed. For example, in 1809, Admiral Nelson's squadron, consisting of 10 ships of the line, crossed the Atlantic Ocean at an average speed of 4.9 kn.

Replica
A 233.3 ft copy of a treasure ship was announced in 2006 to be completed in time for the 2008 Olympic Games. However, the copy was still under construction in Nanjing in 2010. A new date of completion was set for 2013; when this dateline failed to be met in 2014, reportedly due to funding issues, the project was put on hold.