Shipbuilding
Shipbuilding is the construction of ships and other floating vessels. In modern times, it normally takes place in a specialized facility known as a shipyard. Shipbuilders, also called shipwrights, follow a specialized occupation that traces its roots to before recorded history.
Until recently, with the development of complex non-maritime technologies during the industrial revolution, a ship has often represented the most advanced structure that the society building it could produce. Some key industrial advances were developed to support shipbuilding, for instance the sawing of timbers by mechanical saws propelled by windmills in Dutch shipyards during the first half of the 17th century. The design process saw the early adoption of the logarithm to generate the curves used to produce the shape of a hull, especially when scaling up these curves accurately in the mould loft.
Shipbuilding and ship repairs, both commercial and military, are referred to as naval engineering. The construction of boats is a similar activity called boat building.
The dismantling of ships is called ship breaking.
The earliest evidence of maritime transport by modern humans is the settlement of Australia between 50,000 and 60,000 years ago. This almost certainly involved rafts, possibly equipped with some sort of sail. Much of the development beyond that raft technology occurred in the "nursery" areas of the Mediterranean and in Maritime Southeast Asia. Favoured by warmer waters and a number of inter-visible islands, boats with water-tight hulls could be developed. The ships of ancient Egypt were built by joining the hull planks together, edge to edge, with tenons set in mortices cut in the mating edges. A similar technique, but with the tenons being pinned in position by dowels, was used in the Mediterranean for most of classical antiquity. Both these variants are "shell first" techniques, where any reinforcing frames are inserted after assembly of the planking has defined the hull shape. Carvel construction then took over in the Mediterranean. Northern Europe used clinker construction, but with some flush-planked ship-building in, for instance, the bottom planking of cogs. The north-European and Mediterranean traditions merged in the late 15th century, with carvel construction being adopted in the North and the centre-line mounted rudder replacing the quarter rudder of the Mediterranean. These changes broadly coincided with improvements in sailing rigs, with the three masted ship becoming common, with square sails on the fore and main masts, and a fore and aft sail on the mizzen.
Ship-building then saw a steady improvement in design techniques and introduction of new materials. Iron was used for more than fastenings as structural components such as iron knees were introduced, with examples existing in the mid-18th century and from the mid-19th century onwards. This was partly led by the shortage of "compass timber", the naturally curved timber that meant that shapes could be cut without weaknesses caused by cuts across the grain of the timber. Ultimately, whole ships were made of iron and, later, steel.
History
Pre-history
The earliest known depictions of shallow-water sailing boats is from the 6th to 5th millennium BC of the Ubaid period of Mesopotamia. They were made from bundled reeds coated in bitumen and had bipod masts. They sailed in shallow coastal waters of the Persian Gulf.4th millennium BC
Ancient Egypt
Evidence from Ancient Egypt shows that the early Egyptians knew how to assemble planks of wood into a ship hull as early as 3100 BC. Egyptian pottery as old as 4000 BC shows designs of early fluvial boats or other means for navigation. The Archaeological Institute of America reports that some of the oldest ships yet unearthed are known as the Abydos boats. These are a group of 14 ships discovered in Abydos that were constructed of wooden planks which were "sewn" together. Discovered by Egyptologist David O'Connor of New York University, woven straps were found to have been used to lash the planks together, and reeds or grass stuffed between the planks helped to seal the seams. Because the ships are all buried together and near a mortuary belonging to Pharaoh Khasekhemwy, originally they were all thought to have belonged to him, but one of the 14 ships dates to 3000 BC, and the associated pottery jars buried with the vessels also suggest earlier dating. The ship dating to 3000 BC was about 75 feet long and is now thought to perhaps have belonged to an earlier pharaoh. According to professor O'Connor, the 5,000-year-old ship may have even belonged to Pharaoh Aha.Austronesia
The Austronesian expansion, which began with migration from Taiwan to the island of Luzon in the Philippines, spread across Island Southeast Asia. Then, between 1500 BC and 1500 AD they settled uninhabited islands of the Pacific, and also sailed westward to Madagascar. This is associated with distinctive maritime technology: lashed lug construction techniques, various types of outrigger and twin-hulled canoes and a range of sailing rigs that included the crab claw sail. The origins of this technology is difficult to date, relying largely on linguistics, the written comments of people from other cultures, including the observations of European explorers at the time of first contact and the later more systematic ethnographic observations of the types of craft in use. There is only a small body of archaeological evidence available. Since Island Southeast Asia contained effective maritime transport between its very large number of islands long before Austronesian seafaring, it is argued that Austronesians adopted an existing maritime technology from the existing inhabitants of this region.File:Lashed-lug planking in the Butuan balangay boat Two.png|left|thumb|Generalized diagram of lashed-lug planking in Butuan Boat Two
Austronesian ships varied from simple canoes to large multihull ships. The simplest form of all ancestral Austronesian boats had five parts. The bottom part consists of a single piece of hollowed-out log. At the sides were two planks, and two horseshoe-shaped wood pieces formed the prow and stern. These were fitted tightly together edge-to-edge with dowels inserted into holes in between, and then lashed to each other with ropes wrapped around protruding lugs on the planks. This characteristic and ancient Austronesian boatbuilding practice is known as the "lashed-lug" technique. They were commonly caulked with pastes made from various plants as well as tapa bark and fibres which would expand when wet, further tightening joints and making the hull watertight. They formed the shell of the boat, which was then reinforced by horizontal ribs. Shipwrecks of Austronesian ships can be identified from this construction as well as the absence of metal nails. Austronesian ships traditionally had no central rudders but were instead steered using an oar on one side.
File:Naga Pelangi building without frames.jpg|thumb|Construction of the Naga Pelangi in 2004, a Malaysian pinas, using traditional Austronesian edge-dowelled techniques. Note the protruding dowels on the upper edges of the planks and the fiber caulking in the seams.
Austronesians traditionally made their sails from woven mats of the resilient and salt-resistant pandanus leaves. These sails allowed Austronesians to embark on long-distance voyaging.
The ancient Champa of Vietnam also uniquely developed basket-hulled boats whose hulls were composed of woven and resin-caulked bamboo, either entirely or in conjunction with plank strakes. They range from small coracles to large ocean-going trading ships like the ghe mành.
3rd millennium BC
Ancient Egypt
Early Egyptians also knew how to assemble planks of wood with treenails to fasten them together, using pitch for caulking the seams. The "Khufu ship", a 43.6-meter vessel sealed into a pit in the Giza pyramid complex at the foot of the Great Pyramid of Giza in the Fourth Dynasty around 2500 BC, is a full-size surviving example which may have fulfilled the symbolic function of a solar barque. Early Egyptians also knew how to fasten the planks of this ship together with mortise and tenon joints.Indus Valley
The oldest known tidal dock in the world was built around 2500 BC during the Harappan civilisation at Lothal near the present day Mangrol harbour on the Gujarat coast in India. Other ports were probably at Kot Bala and Dwarka. However, it is probable that many small-scale ports, and not massive ports, were used for the Harappan maritime trade. Ships from the harbour at these ancient port cities established trade with Mesopotamia. Shipbuilding and boatmaking may have been prosperous industries in ancient India. Native labourers may have manufactured the flotilla of boats used by Alexander the Great to navigate across the Hydaspes and even the Indus, under Nearchos. The Indians also exported teak for shipbuilding to ancient Persia. Other references to Indian timber used for shipbuilding is noted in the works of Ibn Jubayr.2nd millennium BC
Mediterranean
The ships of Ancient Egypt's Eighteenth Dynasty were typically about 25 meters in length and had a single mast, sometimes consisting of two poles lashed together at the top making an "A" shape. They mounted a single square sail on a yard, with an additional spar along the bottom of the sail. These ships could also be oar propelled. The ocean- and sea-going ships of Ancient Egypt were constructed with cedar wood, most likely hailing from Lebanon.The ships of Phoenicia seem to have been of a similar design.