Gavin Menzies does not look robust enough to take the brickbats that are surely coming his way.
Six years ago, the retired submarine commander caused apoplexy among historians with his controversial theory that vast fleets of Chinese adventurers in multi-masted junks beat Christopher Columbus to the Americas and mapped the entire world centuries before the European explorers. It made him rich and infamous.
Whole websites sprang up devoted to debunking his claims. Scholars called him a fantasist.
Felipe Fernandez-Armesto, professor of history at the University of London, dismissed his book, 1421: The Year China Discovered the World, as "the historical equivalent of stories about Elvis Presley in Tesco and close encounters with alien hamsters".
But while boiling oil was being poured on him from the ramparts of academe, Menzies's book was surging up the bestseller list. It has sold a million copies worldwide, and run to 24 editions in 135 countries.