LONDON, March 16: An amateur British historian who has made headlines by contending that the Chinese reached America 70 years before Christopher Columbus has presented new evidence to support his theory.

If proven true, Gavin Menzies’ contentions could prompt a rewriting of some of the most cherished theories in history books, but academics said they were not yet convinced.

Speaking in London late on Friday, the 64-year-old retired Royal Navy submarine commander also tried to debunk another milestone claimed by Europe — saying that early maps and recalculated star charts showed Chinese sailors circumnavigated the globe 100 years before Portugal’s Ferdinand Magellan.

Menzies said archaeological finds and contemporary accounts supported his thesis that the Chinese mapped the world between 1421 and 1423 before destroying most of their records and abandoning global seafaring in the mid-15th century.

“In every continent of the world there are carved stones describing foreign people arriving and their ships being wrecked,” he said.

Academics at the private presentation at the Royal Geographical Society said Menzies presented insufficient evidence to back his theory.

Menzies said he had located the wrecks of Chinese Admiral Zheng He’s 1421-3 fleet in the Caribbean, but would not reveal their whereabouts until he had published a book on his findings.

Historians agree that Zheng He’s ships reached Africa and may have rounded the Cape of Good Hope.

Menzies said the Chinese admiral’s 107-strong fleet split up and went much further, exploring near the North and South Poles and crossing the Atlantic and Pacific Oceans, plotting the position of stars vital for navigation on their way.

Menzies displayed 15th- and 16th-century European maps that he said showed parts of the Caribbean, America and Australia long before the European explorers reached the New World.

The only possible source for the information in these maps, he said, was the Chinese.

“If people disagree with me they have got to come up with an alternative scenario — I say there is none,” he said.

Menzies said the Chinese discoveries passed to early Western mapmakers through the Portuguese, by way of an Italian traveller, Nicolo da Conti, who went on the Chinese voyages.

Menzies issued 17 pages of “supporting evidence” to back his findings, including lists of Ming porcelain and stone monuments found along the fleet’s course, accounts of contemporary historians and surviving Chinese maps and star charts.

Academics at the event said they could not review Menzies’ thesis properly until he published his promised book.

“It’s a question of building one hypothesis on top of another and constructing a tower of hypotheses”, said Tim Barrett, professor of East Asian History at London University’s School of Oriental and African Studies.

“Even if some of the cartographic evidence about the discovery of America before Columbus is proven, to link that to the Chinese is still another step,” he added.—Reuters