Thames sailing barge

A Thames sailing barge was a type of commercial sailing boat common on the River Thames in London in the 19th century. The flat-bottomed barges were perfectly adapted to the Thames Estuary, with its shallow waters and narrow rivers.

The barges also traded much further afield, to the north of England, the South Coast and even to continental European ports. Cargoes varied enormously: bricks, mud, hay, rubbish, sand, coal and grain, for example. Due to the efficiency of a Thames barge's gear, a crew of only two sufficed for most voyages, although by today's standards it would have been hard physical work at times.

The vast majority of barges were wooden hulled (although a significant number were also built in steel), between 80–90 ft (24–27 m) long with a beam of around 20 feet (6 m). The hull form was as distinctive as their rig, being flat-bottomed with a degree of flare to the sides and plumb ends. The stern was a transom, shaped like a section through a champagne glass, on which was hung a large rudder. The hull was mainly a hold with two small living areas in the bow and stern, and access was through two large hatchways, the smaller before the main mast and a much larger aperture behind.

They were usually spritsail rigged on two masts. Most had a topsail above the huge mainsail and a large foresail. The mizzen was a much smaller mast on which was set a single sail whose main purpose was to aid steering when tacking. The rig also allowed a relatively large sail area on the upper part of the mast, to catch wind when moored ships, buildings or trees blocked wind on the water's surface. Sail areas varied from 3000-5000 sq ft (278.8-464.5 sq m) depending on the size of the barge. The typical, rusty-red colour of the flax sails was due to the dressing used to waterproof them (traditionally made from red ochre, cod oil, and seawater). No auxiliary power was used originally but many barges were fitted with engines in later years.

...
Wikipedia