LYCOS RETRIEVER 
Navy
built 238 days ago
Navy ships normally operate with a group, which may be a small squadron of comparable ships, or a larger naval fleet of various specialized ships. The commander of a fleet travels in the flag ship, which is usually the most powerful vessel in the group. Prior to the invention of radio, commands from the flag ship were communicated by means of flags. At night signal lamps could be used for a similar purpose. Later these were replaced by the radio transmitter, or the flashing light when radio silence was needed.
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