Dhow (dhau) is a generic term, covering a number of similar ship types that have plied the northern Indian Ocean and attached waterways since antiquity. In its original strict meaning it was a trading vessel of up to about 200 tons, lateen rigged on a single mast, developed in the first centuries A.D. by the Arabs.
Vessels of the dhow family, with names depending on the time and location of their use, but of similar shapes, and using similar construction techniques (originally with the strakes (planks) of the hull sewn together) dominated trade in the Indian Ocean until the arrival of the Portuguese at the turn of the 16th century. Trade using dhows ranged from the coast of modern Mozambique to Canton (Guangzhou) and other ports in China.
Notable examples are:
- The two masted Arabian baggala of 100 to 400 tons displacement, used for fishing, trade or war, that flourished from the 17th to 19th century. It was settee rigged on a mainmast and small mizzen. Like all dhows, the bow was extremely raked, right down to the keel.
- The battela was a two masted Indian variety used both for coastal and deep-water trade.
- The bûm is a common type, carrying two masts with the usual settee sails. It could be up to 37 metres long. It originated in Kuwait but is still used around much of the coast of the Arabian peninsula. Whilst these days, in most cases the sails have been replaced by diesel engines, in 1980, traditional sewing techniques were used to construct a bûm, the “Sohar”, which voyaged successfully from Oman to Canton, China under sail.
- The 2 or 3 masted Arabian ghanja is similar to the Indian kotia. Designed as fast freight vessels, they were much used by pirates.
- The mtepe is an east African variation of the dhow that is unique in that it carries a square sail made of bamboo matting. It also carries a small hut aft of the single mast. It was still being constructed during the 20th century.
- The Indian pattamar was a sturdy teak-hulled trading vessel with up to three masts. The larger varieties were decked. Their underwater hull design, and the mixed settee and gib rigging, gave them exceptional sailing characteristics; so much so that they are still seen today along the east Indian coast, and some specialised sailing yachts have copied their design.
References: "The Oxford Companion to Ships and the Sea"|"Dictionary of Ship Types" (Conway Maritime Press, 1986