Shipwrecks


Anchors

wooden-stocked anchor
An old-style wooden-stocked anchor stowed alongside on a sailing ship. Note the two hawsepipes where the mooring chains enter the bow.

Not all artifacts are easily recoverable. Ship's anchors often weigh in the hundreds or thousands of pounds and require a well-planned expedition to bring back to shore. At right is an assortment of anchors, from the old-fashioned "Fisherman's" anchor of the 1800s to the modern stockless or "naval" anchor, and its small cousin, the Danforth anchor.


paddlewheel

The paddlewheel predates even the steam engine. Horse-driven paddlewheel ferries have been in use for hundreds of years. Compared to screw-type propellers, the design and construction of a paddlewheel is much simpler, and therefore they remained the dominant method of propulsion through the mid-1800s, with some examples remaining in use until after World War II.


Scotch boiler ( cutaway )
A typical Scotch boiler ( cutaway )

Boilers are one of the most common shipwreck features, found on almost all engine-powered vessels. The purpose of a boiler is to produce high-pressure steam for the engine to propel the vessel. Steam boilers have been in use from the early 1800s to the present day.


Wooden Ship Framing
Wooden Ship Framing

Wooden ships have been constructed for thousands of years. Around the world, many different construction techniques have been used, some of them quite extraordinary. The ancient Greeks stitched the planks of their warships together edgewise to form an extremely light frameless load-bearing shell, much like a modern airplane fuselage. However, most wooden ships are built using a basic framing system that has changed little over the centuries.


shipwreck SS Delaware engine

Steam Engines

Steam engines are a common sight on New Jersey shipwrecks. Usually the highest point of relief on the entire wreck, the engine makes a good orientation point and is often used as a tie-in as well. Old steam engines were quite sturdily constructed, and last a long time in the ocean, although because of their value they were salvaged when possible.

Right: The single-expansion steam engine of the Delaware, viewed over the top of one of the four boilers.


composite ship construction

Iron and steel began to replace wood in ship construction in the middle to late 1800s. Timber-poor Europe ( especially England ) led in the development of iron ships, while America, with its vast reserves of lumber, continued to build wooden ships for some time longer. However, as the economical size of ships grew to surpass what could be built of wood, America too began constructing iron ships. For a few years, composite ships were built with iron frames and wooden skins, as seen at right, but difficulties with corrosion between the wood and metal soon led to hulls built completely of metal, both sailing ships and steamers.


Common Atlantic Octopus

Octopus vulgaris

Size: see below

Habitat: rocks and coral reefs, all depths

Notes:

The Common Octopus is the most studied of all octopus species. Its natural range extends from the Mediterranean Sea and the southern coast of England to at least Senegal in Africa, as well as the Azores, Canary Islands, and Cape Verde Islands. In the western Atlantic, it ranges from Texas and Florida to New England, although uncommon in colder northern waters. Typical habitat is rocks and coral reefs. Young are planktonic, and total lifespan is only 12-18 months.

O. vulgaris grows to 25 cm in mantle length with arms up to 1 m long. They can weigh up to 20 pounds, although they are usually much smaller. O. vulgaris is caught by bottom trawls on a huge scale off the northwestern coast of Africa. More than 20,000 tons are harvested annually.