Zheng He May Not Have Been So Adventurous

One of the many aspects of the current surge in officially-guided Chinese nationalism is a focus on the seafaring achievements during the Ming dynasty. Top of the list are the voyages of the early Ming envoy Zheng He around the Indian Ocean and to the coasts of Arabia and east Africa.

Accompanied by a flotilla of large ships carrying several thousand soldiers as well as seamen, these are mostly described as peaceful voyages of diplomacy and discovery. Other Ming-era accomplishments are said to include the use of the magnetic compass for navigation, a technique then probably borrowed by Arab, European and Japanese navigators.

However, other research now suggests that many of the claims for the Ming era achievements have been exaggerated. Chinese-reading academic experts seem to have taken literally statements in official documents without either the experts or the documents’ authors having any knowledge of such practical issues as ship construction and conditions at sea. The net effect may well be to over-emphasize the role of the likes of Zheng He and other official representatives of the emperor and downplay the role of private Chinese traders in the commerce of southeast Asia and its links to India, the Arab world and the west, and to Okinawa and Japan.

The former director of the Hong Kong Maritime Museum, Stephen Davies, was recently heckled at a symposium on Ming era maritime issues for daring to suggest that though the Chinese had an early understanding of the magnetic compass, the instrument only became useful for navigational purposes as a result of a series of technical improvements made mainly in Europe, over several hundred years.

Davies concluded that “the magnetic compasses carried aboard Ming Dynasty vessels (and equivalently equipped vessels elsewhere) cannot have been reliable navigational aids and that no prudent mariner would have used them as such”.

In reality, he argued, the Ming-era sailors, like their Arab, Bugis, Polynesian and other contemporaries relied on a well-proven traditional methods of navigation using sun and stars, known landmarks and birds and other natural evidence.

Unlike the Polynesians and some voyageurs across the Indian ocean they mostly hugged coastlines and were seldom more than 200 miles from a landmark of some sort.

In a highly technical paper, Davies, a former naval officer, map maker, historian and sailor, describes the huge difficulties of achieving sufficient accuracy for a compass on board a ship to be of use other than showing very general direction of north. Typical Ming examples could not provide the degree of accuracy needed to be superior to traditional methods.

Indeed, Davies argues, almost as soon as magnetic compasses reached a very high degree of accuracy, in the late 19th century, they were superseded by gyroscopic ones.

Compasses first went to sea in China around the 12th century with a magnetized needle sitting in a bowl of water. The technique was soon also used by Arab and European sailors and improvements came gradually – a dry pivot for the needle, a lubber line to provide a constant reference point and eventually gimbals to steady the apparatus.

However even on land, accuracy to within 10 degrees was about the best that could be hoped for.

Chinese mariners early on roughly understood variation – the variable amount by which magnetic north differs from true north, but not deviation, the inaccuracies created by other nearby magnetized objects -- in the case of Chinese ships the iron nails used extensively in construction, and possibly also of some of the ship’s cargo.

But the biggest problem was keeping the instrument steady while at sea, a vessel being subject to pitching, rolling and yawing under the impact of waves and wind. This was compounded by the Ming (and internationally general) practice of keeping the compass high up on the poop deck at the rear of the vessel rather than at the ship’s center of gravity where motion was least.

Nor was there understanding of or compensation for other variables such as lateral oscillation and vertical declination of the needle – especially a weakly magnetized one.

No actual examples of a Ming era compass used at sea exist and, according to Davies, suggestions that a form of gimbals was achieved by using bowls within bowls would not have worked even if it had been tried.

Indeed absence of actual examples bedevils other aspects of Ming era navigation, not least the ships that Zheng He sailed to Southeast Asia and around the Indian ocean.

These were said, in an account written centuries later, to have measured 44 zhang or 137 meters in length. This has been widely accepted by scholars but challenged by experts in shipbuilding who doubt the feasibility of wooden ships that large. Certainly no remains have been discovered and the largest known wooden Chinese vessel was about 70 meters. An attempt to replicate a 71 meter version of a Zheng He “treasure ship” – still only half the size of the largest claimed in Chinese texts – has been put on hold. It was also, for regulatory reasons, using western “frame first” techniques, not traditional Chinese ones.

Zheng He, a Muslim eunuch from Yunnan was a commander of forces in military campaigns at home before being given charge of a large fleet with several thousand men to visit Southeast and South Asian, Arab and eventually east African ports.

There is no doubt that Zheng He’s massive fleets and repeated voyages – seven in all – made a huge impression around the region. How purely peaceful and purely diplomatic they were is debatable given their role in suppressing what Chinese chroniclers called pirates, and intervening in local disputes.

Diplomacy alone would scarcely require such a vast, heavily armed fleet. Even though the voyage program ended abruptly it left a legacy, especially in Malacca, and may also have helped the spread of Islam in Southeast Asia. Indeed some claim that this soldier was in reality a peaceful missionary for Islam.

Yet these and other claims made for Zheng He as a great navigator and explorer seem much exaggerated. Other peoples had been sailing and trading across the Indian ocean and down the coast of Africa for a thousand years or more before Zheng He, and had developed astronomical data for calculating latitude and direction. The spice islands of eastern Indonesia traded with Rome via southern India by around year 100 of the current era. The Greeks knew of Zanzibar by that time, Malays, probably from Borneo, settled Madagascar around 500 CE, Persians colonized Zanzibar around 700CE, Butuan in Mindanao was trading with India around 1,200CE, etc

Indeed, many of the claims made for Zheng He and for other Ming achievements are possible only because of ignorance of the achievements of others – or by extrapolation from Chinese documents written years later by chroniclers with a limited understanding of issues or eager to flatter the throne.

China’s current liking for inventing or exaggerating its own history while forgetting others’ histories is part of a nationalist agenda which would rather shout down scholars than address real issues of fact such as the history of trade and seafaring in the South China Sea and Indian ocean.