July 10th 1405 is the supposed date of departure for the first of the “discovery” voyages of Admiral Zheng He. There is a lot of hyperbole given out about these voyages and many Chinese compare them to the European voyages of discovery. There is also a lot of boasting about the size of the ships involved.
Zheng He was a Muslim eunuch, scion of a famous Persian lineage which served the Mongol Empire.
The notion that he “discovered” anything is a little silly. The Arabs had been sailing the seven seas since Sinbad was a boy in the 9th century and by the 15th Century when Zheng He weighed anchor their trade routes were well documented. All he did was follow the Arabic trade routes to establish the bona fides of the Chinese Court from Africa to the far East.
The other great claim is that he built the largest wooden ships in the world. It may be true that they were the largest when they were sailing, but it is debatable if they were as big as claimed. There are limits to the size of vessels imposed by physics. The largest documented wooden sailing ship, the Wyoming at 137 metres, was a six masted schooner built in 1909 in Maine, USA. She suffered horribly from hogging and sagging in heavy seas.
Hogging occurs when a ship is on top of a wave supported by the middle section. A very long ship can bend down at the fore and aft sections, since they are unsupported. The opposite, sagging, occurs when the fore and aft are supported on two waves, leaving the mid-ship suspended, causing the vessel to sag in the middle.
The cumulative effect of hogging and sagging over time is to twist the planking in the hull, causing leaky seams. Wyoming needed constant work at the pumps to keep her from flooding. She eventually sank in heavy seas in 1924.
The Chinese claim Zheng He’s flagships, his nine masted treasure ships, were even longer and much wider than the Wyoming. They probably employed a very different type of construction, far bulkier and more rigid. Also the nine masts were likely far shorter than those of an American Schooner. Chinese Junk Rigs use shorter masts with fully battened sails. It would be no surprise that a ship the length of Wyoming would need more, shorter masts to drive it.
The fleet of 317 ships carrying 30,000 men was undoubtedly impressive and you get the sense that these voyages were intended to leave the world in awe of the power of the Ming dynasty. The intention may have been to exert Chinese control over the Indian Ocean trade.
Ultimately it was not the Chinese who subdued the Indian Ocean. Vasco da Gama returned to Portugal from India in 1499, just scraping in as the 15th Century voyager who had the most significant impact on world history. He set out with 4 ships, none longer than 30 metres, and 170 men. Sometimes size is not everything.