SS Jeremiah O'Brien is a World War II-vintage cargo ship designated in U.S. Maritime Commission nomenclature as an EC-2 type ("E" for "emergency," World War II being the emergency which caused design and construction of the type; "C" for "cargo," and "2" designating a large capacity). She was the product of a standardized design, adapted from the design of an old and timeproven British tramp ship which originated in 1879. Based on plans obtained from Sunderland, England, the New York naval architect firm of Gibbs and Cox and the U.S. Maritime Commission drew the detailed plans for liberty ships. When shown the plans in 1941, President Franklin D. Roosevelt approved the efficiency of the proposed design but commented that the resulting ship would be "a real ugly duckling," a comment picked up and disseminated by the press and adopted by many. 
The standard liberty ship, including the SS Jeremiah O'Brien, was 441 feet and 6 inches in length, with a bean of 56 feet, gross tonnage about 7,176, and displacement tonnage 14,300. The ship was designed to carry 9,146 tons of cargo with a full load of fuel. Commonly they carried more, with holds filled and in addition a deckload of planes or tanks, crated aircraft or trucks, heavy. machinery or railroad locomotives, or a combination of these cargoes, loading them down to their Plimsoll marks or beyond with a 10,000-ton payload. On occasion the ships were used as troop transports. The ship was designed for a crew of 44, but frequently had in additional naval armed guard of ten or twenty or more, making the quarters cramped.
SS Jeremiah O'Brien is a cargo vessel with a raked stem, flush deck, and cruiser stern. Her machinery is amidships. There are five cargo holds, three forward of and two aft of the machinery space. Salt water ballast or dry cargo can be carried in deep tanks provided in Nos. 1 and 4 holds. Cargo handling was by steam winches with booms stepped at the masts and at a center line kingpost. Natural ventilation ducts lead to all holds.
The main propelling machinery consists of a triple expansion steam reciprocating engine, size 24-1/2 x 37 x 70 x 48 inches, manufactured by General Machinery Corporation, developing 2500 IHP at 76 RPM and supplied with steam at 220 lbs. per square inch pressure and 440°F temperature at the throttle operating on 27" vacuum. The steam was created by two oil-fired water-tube boilers, manufactured by Foster-Wheeler, of the cross-drum, sectional header type. She is equipped with three reciprocating steam driven 20 K.W. generators, two Worthington designed boiler feed pumps, an enclosed crank-case type reciprocating engine driven forced draft fan and main circulator. Fire, bilge, ballast, general service, and fuel oil service pumps are principally of Worthington design and/or manufacture.
SS Jeremiah O'Brien is in excellent condition, retains her World War II integrity, and is mechanically operational.
Role of the Liberty Ship in World War II
"Liberty Ships" were an emergency response to a critical shortage of maritime cargo ships in World War II. Their construction was a significant accomplishment in engineering design for mass production, and the ships were built to a high standard of performance for the time and under the conditions of wartime emergency. Manned by merchant seamen for the most part, they carried all kinds of wartime cargo, including food, fuel, ammunition, weapons and all kinds of supplies, through the Atlantic and Pacific Oceans, the Mediterranean Sea, the Persian Gulf and elsewhere. Approximately 2,742 liberty ships were built during the war. By 1945 liberty ships comprised the greatest standardized fleet in world history. 
Some liberty ships were operated by the U.S. Navy and used to supply landings such as the Invasion of Normandy where some of these ships were deliberately scuttled to form breakwaters called "gooseberries," while others supplied the troops on the beaches. Others were used by the Army Transport Service. A few were converted to serve as hospital ships. During the war they typically were armed for defense and many participated in combat involving attacks by enemy submarines and aircraft. More than 200 were sunk by enemy torpedoes or bombs or in storms at sea, while others survived attacks with varying amounts of damage.
SS Jeremiah O'Brien represents the class of liberty ships that contributed to victory in World War II for the following reasons:
T. J. Patterson, Jr. and Gordon Chappell, "National Register of Historic Places Inventory SS Jeremiah O'Brien" (San Francisco, California: U.S. Maritime Administration, 1978)
Bunker, John Gorley. Annapolis, Maryland: Liberty Ships--The Ugly Ducklings of World War II. Naval Institute Press, 1972.
Patterson, T. J. Jr., and Chappell, Gordon. "National Register of Historic Places Inventory SS Jeremiah O'Brien." San Francisco, California: U.S. Maritime Administration, 1978.
(click on the above photographs for a more detailed view)