Video Episode - In Search of Ships of the Civil War
Hunt for the U.S.S. Preble
The U.S.S. Preble was built in 1838 as a navy sloop-of-war at the Portsmouth shipyard. The Preble was a Dale 3rd Class ship built out of wood just prior to the age of steamships. She was able to carry 16 carronades (32 – pounders) during times of peace and was able to have two long guns for war. The basic dimension of the dale class ships are as followed: Length – 117’7”, Beam – 32’0”, Depth of hold – 15’0”, Tonnage 566, 3rd Class.
The Preble was commissioned on 2 June 1840. After a year of waiting, the Preble began her long career sailing around Labrador, the Mediterranean, Africa, India, China, Japan and the United States. The Preble was a part of the Mexican War in 1847. She was also used as a training vessel by the US Naval Academy placed in ordinary which meant that her guns, mast, sails, and rigging were removed. The Preble was place on active duty during the Civil War where she was a part of the West Gulf Coast Blockade Squadron for the Union. In September 1862 the Preble was Stationed at Pensacola to help stop privateers. She caught on fire on 27 April 1863 and sank to the bottom of Pensacola Bay. Because the Preble had her guns, mast, sails, and rigging removed prior to the civil war, the full extent of her armament may not match what was originally planned for her. She might have had some modifications to her mast, rigging, sails, and or guns of any were ruined from the 5 – 6 year period she used by the US Naval Academy.
Her final wreck site is still unknown to archaeologist though the US Navy has done some dives on what has been called the Preble in the 1960’s. The Navy divers removed a mast and some other objects before leaving the Preble alone.
This summer, in an effort to relocate the Preble, multiple survey techniques will be employed. However, before any survey can be completed, hours of extensive research must be done to attempt to narrow down the survey area. That way the survey technicians can search in the right area for the wreck, it does not make any sense to search in Blackwater Creek for a ship that could only use the main channels in Pensacola Bay!
After the research is done, the survey crew will use a technique called side scan sonar. This is when a sonar device, called a fish, is towed behind the survey vessel. It emits pulses to either side and the operator can choose how far away they want to measure. The further the pulses go, the less accurate they are. The images produced by the fish are relayed back to a computer on deck where the team can search of anomalies such as really bright spots and dark shadows. Surprisingly detailed, it is possible to see depressions in the bottom from shrimp nets and anchor lines and even items as small as a bike! The fish is pulled behind the boat in preset lines using a GPS mapping system.
If an anomaly is found, such as a large structure or a very bright spot, then divers are sent in to do target diving. They will descend on the GPS coordinate and systematically search the surrounding area to find any objects or structures of interest. If the divers find anything, they record the site with that national registry to ensure legalities. Properly trained divers and archaeologists will continue to examine the site!
Contributors: K. Bender and C. Giles