The Dewey Medal was created to recognize the forces of the U.S. Navy and United States Marine Corps who participated in the Battle of Manila Bay. To be awarded the Dewey Medal, a service member must have served in one of the following naval vessels on May 1, 1898
U.S.S. Baltimore
U.S.S. Boston
U.S.S. Concord
U.S.S. McCulloch
U.S.S. Nanshan
U.S.S. Olympia
U.S.S. Petrel
U.S.S. Raleigh
U.S.S. Zafiro
The Dewey Medal was a one time only decoration and there were no devices or campaign stars authorized to the medal. The medal consists of a circular medallion, upon which rests an image of Admiral George Dewey, suspended from a blue and yellow ribbon. Admiral Dewey himself was awarded the medal, although he always wore it with the medal's reverse displayed which depicted a Navy gun crew.
Although recognized as an active military duty, because the Dewey Medal recognized a single battle in a single campaign, the medal quickly became regarded as a commemorative medal and did not appear on U.S. Navy and Marine Corps precedence charts. When worn on a military uniform, however, the Dewey Medal was considered equal to the Spanish Campaign Medal and senior to the Sampson Medal.
Dewey joined the ship in Boston on May 10, 1861, and a few days later he was on his way south to join the Union blockade in the Gulf of Mexico.
Dewey's years at the head of the bureau saw the introduction of such devices as electric searchlights and signaling apparatus in all ships of the navy, as well as the introduction of a modern engine-room telegraph system, which enabled officers on the ship's bridge to order small variations in speed to the engine room.
Dewey also succeeded in increasing the bureau's appropriation of funds from Congress to augment the coal allotment, owing to the fact that the newer ships were more dependent on steam engines than older vessels, which primarily relied on sails.