Chinese Junk

The Chinese Junk is a wooden ocean going vessel that has been in continuous use for over 2,200 years.
It was in use during the Roman Period, and was first written about during the Han Dynasty (206 BCE-220 CE).

It differed from Roman ocean going vessels by having a central stern mounted steerable rudder and sails that could be rotated through 180 degrees.
This allowed a Junk to sail close hauled and tack through the wind, whereas square-rigged Roman vessels had to ‘wear about’ and turn through 270° to change direction.

Wan Chen describes Junks in circa 250 CE, carrying 250 tons of cargo and 700 people.
Kang Tai describes Junks with seven masts in 260 CE, sailing to Syria.
One Junk excavation site dates the iron nails to 221 BCE.
The first pottery model of a Junk appears to date from the first century CE.
The Geographer Ptolemy wrote that Roman Merchants traded in Silk from China, with the port of Kattigara.
Kattigara is thought to be the archeological site of Oc Eo in Vietnam.

Hull:
- The River Junk
  - This had a flat bottom with no keel. Instead of a keel, a large rudder was used to prevent the vessel slipping sideways. Sometimes a daggerboard or leeboard was used.
- The Ocean Junk
  - This had a curved hull with a wide beam at water level which narrowed as it reached the top deck.
- Bulkheads
  - The Junk was built with separate compartments divided by bulkheads which were accessed by individual hatches.
  - It is thought these were watertight, making the Junk virtually unsinkable.
Sails:
- Each sail has several wooden battens which are controlled by trailing lines. The sails can be reefed in strong winds.
- They could also be turned to align with the keel, permitting the vessel to sail close to the wind and then tack through the wind. No Roman vessel could tack through the wind, but had to ‘wear about’.
Rudder:
- a single stern mounted rudder that could be raised when in shallow water, but needed several men to control it in strong winds.

The Rudder:
- The stern mounted rudder acted partly as a keel and could be raised in shallow water.
- The Romans used a pair of oars on either side of the vessel’s stern for rudders.
The Sails:
- These could be aligned with the longitudinal axis of the ship, permitting sailing close into the wind.
- A Roman cargo vessel could not sail more than about 80° into the wind.
- The sails could also swivel 180° around the mast, permitting tacking through the wind.
- A Roman vessel would have to ‘wear about’, ie turn away from the wind and continue turning until it came close to about 80° into the wind from the opposite direction.
Bulkheads:
- The junk was constructed with separate compartments using bulkheads. As with modern Junks, this would probably have provided watertight sections, allowing the Junk to survive serious storms.
- Roman vessels were vulnerable to sinking if caught by a storm.

South China Sea