Reinforcement for Fort Pickens.
--A dispatch from Washington, dated the 4th inst., says:‘ Lieut. Gilman was last week sent to Pensacola, with dispatches for the commander of the United States steam-sloop Brooklyn, directing him not to transfer the troops on board his vessel to Fort Pickens until after the third inst. It is presumed, therefore, that the garrison of Fort Pickens will be reinforced to-day, as the captain of the Brooklyn is anxious to get rid of his large company as soon as possible.
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