LONDON (Reuters) - Leonardo da Vinci's drawings of machines are uncannily similar to Chinese originals and were undoubtedly derived from them, a British amateur historian says in a newly-published book.

Gavin Menzies sparked headlines across the globe in 2002 with the claim that Chinese sailors reached America 70 years before Christopher Columbus.

Now he says a Chinese fleet brought encyclopedias of technology undiscovered by the West to Italy in 1434, laying the foundation for the engineering marvels such as flying machines later drawn by Italian polymath Leonardo.

"Everything known to the Chinese by the year 1430 was brought to Venice," said Menzies, a retired Royal Navy submarine commander, in an interview at his north London home.

From Venice, a Chinese ambassador went to Florence and presented the material to Pope Eugenius IV, Menzies says.

"I argue in the book that this was the spark that really ignited the renaissance and that Leonardo and (Italian astronomer) Galileo built on what was brought to them by the Chinese.

"Leonardo basically redrew everything in three dimensions, which made a vast improvement."

If accepted, the claim would force an "agonizing reappraisal of the Eurocentric view of history", Menzies says in his book "1434: The Year A Magnificent Chinese Fleet Sailed To Italy and Ignited The Renaissance".

NONSENSE

The urbane 70-year-old sold more than a million copies of his first book, "1421", which argued Chinese sailors mapped the world in the early 1400s shortly before abandoning global seafaring.

His theories are dismissed as nonsense by many academics -- Menzies says Chinese fleets reached Australia and New Zealand as well as America before European explorers -- but have gained an international following among readers.

"This whole fantasy about Europe discovering the world is just nonsense," said Menzies.

In his latest book -- published in the United States in June and this month in Britain -- Menzies says four ships from the same Chinese expeditions reached Venice, bringing with them world maps, astronomical charts and encyclopedias far in advance of anything available in Europe at the time.

Menzies says Leonardo's designs for machines can be traced back to this transfer of Chinese knowledge.

Leonardo, born in 1452, is perhaps best known for his enigmatic "Mona Lisa" portrait of a woman in Paris's Louvre Museum, but he also left journals filled with intricate engineering and anatomical illustrations.

Menzies says designs for gears, waterwheels and other devices contained in Chinese encyclopedias reached Leonardo after being copied and modified by his Italian antecedents Taccola and Francesco di Giorgio.

To support his argument, Menzies publishes drawings of siege weapons, mills and pumps from a 1313 Chinese agricultural treatise, the Nung Shu, and from other pre-1430 Chinese books, next to apparently similar illustrations by Leonardo, Di Giorgio and Taccola.

"By comparing Leonardo's drawings with the Nung Shu we have verified that each element of a machine superbly illustrated by Leonardo had previously been illustrated by the Chinese in a much simpler manual," Menzies writes.

"It's very suggestive, very interesting, but the hard work remains to be done," said Martin Kemp, Professor of the History of Art at Oxford University and author of books on Leonardo.

"He (Menzies) says something is a copy just because they look similar. He says two things are almost identical when they are not," Kemp said.

"It's not strong on historical method," he added. But Kemp said he would look out for any signs that Leonardo had access to Chinese material, directly or indirectly, when studying his manuscripts in future.