state that the European East Indiamen and galleons were 30, 40, 50, and 60 zhang (90, 120, 150, and 180 m) in length. The length of a Dutch ship recorded in the History of Ming was 30 zhang. If the zhang is taken to be 3.2 m, the Dutch ship would be 96 m long. Also, the Dutch Hongyi cannon is recorded to be more than 2 zhang (6.4 m) long. A comparative study by Hu Xiaowei (2018) concluded that 1 zhang would be equal to 1.5–1.6 m, this means the Dutch ship would be 45–48 m long and the cannon would be 3–3.2 m long. Taking 1.6 m for 1 zhang, Zheng He's 44 zhang treasure ship would be long and wide, or 22 zhang long and 9 zhang wide if the zhang is taken to be 3.2 m. It is known that the measuring unit during the Ming era was not unified: A measurement of East and West Pagoda in Quanzhou resulted in a zhang unit of 2.5–2.56 m. According to Chen Cunren, one zhang in the Ming Dynasty is only half a zhang in modern times. 5,000 liao ship In June 2010, a new inscription was found in Hong Bao's tomb, confirming the existence of the Ming dynasty's 5,000 liao ship. Taking the liao to be 500 lbs, that would be 1,250 tons burthen. According to Zheng Ming, the 5,000 liao ship would have a dimension of , width of , with draught, and the displacement would reach more than 2,700 tons. The 5,000 liao ship may have been used as the flagship but the number of ships was relatively small. Wake argued that the 5,000 liao ships were not used until after the 3rd voyage, when the voyages were extended beyond India. Xi Longfei identified that the word "treasure ship", which would refer to the 44 zhang ship, appeared for the first time in the 6th year of Yongle. This large ship was too late to be used for the third voyage, so it appeared for the first time during the 4th voyage, and was recorded by Ma Huan. Judging from the three images from the Ming era, the largest ships had 3–4 main masts and 2–3 auxiliary masts. Structure The keel consisted of wooden beams bound together with iron hoops. In stormy weather, holes in the prow would partially fill with water when the ship