Underwater Archaeology

History of Underwater Archaeology

Based on first-hand accounts the approximate position of the Hamilton and the Scourge was known but the depth of water in the lake prohibited exploration for years.

Diving technology began to be developed in the 1940s when the Aqualung was invented by Jacques Cousteau and Emile Gagnan; this enabled the systematic exploration of nautical sites.

The formal techniques of nautical archaeology were pioneered by George Bass and his colleagues in the 1950s.

The Swedish Museum of Maritime History was the first to list marine archaeology as one of its regular activities. Its first activity was to locate the Wasa at the bottom of Stockholm harbor, located in 1956. The wreck was raised in 1961 and can be visited today.

Archaeology of Deep-water Sites

Problems involved with the investigation and excavation of deep underwater sites can be overcome using ROVs, which stands for 'remotely operated vehicles'. ROVs were used to investigate a 4th century merchant ship in the Mediterranean by Robert Ballard in the late 1980s. 'Jason', a robot craft operated from the surface, was used to photograph the wreck and retrieve artifacts from the seabed at a depth of about 2,500 feet below the surface. By using ROVs, there is no risk to human life, with the potential for unlimited access to deep underwater sites.

Techniques such as stereophotography permit the recreation of three dimensional forms. This technique was used on the Arles IV wreck, a 1st century A.D. ship sunk off the southern coast of France. In 1989 and again in 1993, stereophotographs brought back clear images of a cargo of 950 amphorae (clay pots) lying on the ocean floor. This photographic technique has eliminated the necessary 'destruction' of a ship that excavation will cause, no matter how carefully controlled that excavation might be.

Archaeology and the Hamilton and Scourge Project

Excerpts from the Archaeological Report by Kenneth A. Cassavoy, 1982

In documenting the material present on the site, a grid plan was superimposed on the plan view. This grid divides the site into 4 metre squares to facilitate archaeological recording of the wrecks. The prime horizontal line runs the length of the vessels through the centre of the foremast, the mainmast and the rudder post with extensions beyond the bow and stern. The prime vertical line runs at a 90 degree angle through the prime horizontal. All other horizontal and vertical grid lines run at a scale 4 metres distance from the prime line.

The ship's guns, considered to be the major archaeological features of the sites, were given individual numbers for ease of reference. The numbering of the guns runs from starboard stern, counter-clockwise around the vessels, ending at the port sternmost gun. The central gun on the Hamilton was designated #9.

Once the grid system had been established, the site was investigated using remotely operated vehicles like those described above.

Archaeology of Other Warships

The Mary Rose

The Mary Rose was the flagship of King Henry VIII of England; the vessel was known to have gone down off the southern coast of England in the sixteenth century. Due in large part to the findings of Alexander McKee, a journalist and amateur diver searching along the southern English coast, the Mary Rose Committee was formed in 1967 to locate, excavate and preserve any remains of the ship. The location and identity of the flagship was confirmed in 1971, and subsequent excavation over the next eleven years, guided by archaeologist Margaret Rule and funded by private industry, government agencies and the Royal family, led to the raising and preservation of the remaining portion of the hull.

Learn more about the Mary Rose.

The Vasa

The Vasa was discovered through the efforts of the Swedish Museum of Maritime History, the first institution to include underwater archaeology among its projects. Working for the museum, Anders Franzén, the chief engineering secretary for the Swedish Admiralty and an avocational marine archaeologist, sought the wreck of the Vasa, a royal warship lying at the bottom of Stockholm Harbour. By August, 1956, the Vasa had been identified and located. The vessel was raised following a five-year combined effort of various sectors of the Swedish government and private industry. The conservation technologies developed after the raising of the Vasa were a model for later preservation attempts by other underwater projects around the world (to learn about the Vasa's conservation, click here).

Learn more about the Vasa.

H.M.S. Tecumseh

The H.M.S. Tecumseh was built in 1815, in the settlement of Chippewa, Ontario, just south of Niagara Falls, Ontario. She was 70'6" in length, 24'5" in breadth and the draught was 7'. She carried two 24 pound guns and had a crew of approximately 30 men.

The Tecumseh was originally designed for defense against the Americans but after the War of 1812 she was put into service on Lake Erie. In 1817 she was stationed at the new naval base at Penetanguishene Harbor to service in Lake Huron.

Soon after the Tecumseh's arrival in Penetanguishene the Rush-Bagot agreement (1817) was signed between the British and the Americans. This agreement limited the number of warships allowed on the Great Lakes by each nation.

Because of the agreement the Tecumseh was put 'in ordinary', meaning her fittings and arms were removed and stored. The vessel was kept at the Penetanguishene naval base, which now served as a naval storage depot. The ship sailed only once more after being put 'in ordinary'. In 1828, the Tecumseh assisted with the evacuation of Drummond Island in 1828 prior to that island being turned over to the United States. The ship was fitted and used to transport people and supplies from Drummond Island to Penetanguishene.

Later in 1828 orders were given to sink the Tecumseh and she was to be struck from the Admiralty's list. But the order came too late as the Tecumseh had already sank earlier in the year in Penetanguishene Harbour.

In 1953, Wilfred Jury, the chief archaeologist at Penetanguishene's Historic Naval and Military Establishment (HNME), now known as Discovery Harbour, arranged for the wreck of the Tecumseh to be raised from the bay and to be put up on shore for display. Throughout the years the wreck has been moved several times for display purposes and now rests under a protective roof.

The wreck of the Tecumseh is quite fragile and because of this, items from the wreck have fallen off or been removed over the years. The hardware recovered from the wreck is kept in storage at Discovery Harbour. A conservation strategy for the wreck is pending.