ON BOARD STEAMER MISSISSIPPI,

Off Hilton Head, S. C., March 12, 1862.

Major General GEORGE B. McCLELLAN,

Commander-in-Chief U. S. Army:

GENERAL: I have the honor to report the causes of my detention at this port, which will be fully set forth in the extracts from itinerary herewith inclosed.

It will be seen that after a series of most unparalleled marine disasters I am at last ready for sea, and shall sail as soon as the weather permits.

I inclose also a copy of an order of arrest of the master of the steamer, by whose faults and mismanagement our misfortunes have been caused.

A competent master and coast pilot have been detailed from the naval squadron to command the ship on the rest of the voyage.

I desire to express my deep sense of obligation both to General Sherman and officers of his command for every aid in our distressed condition. Thanks are especially due to Commander Boutelle, assistant, U. S. Coast Survey, for the very efficient assistance given by the steamer Bibb, under his command, and the untiring personal exertions in giving his services and those of his officers, at my request, to get this ship in a condition for sea, and also in acting as pilot to get her off a shoal on which she had grounded in our attempt to get to sea.

A board of survey of competent naval officer have pronounced the ship fit for sea, and I have no further fear of her, under a competent commander. No serious casualty has occurred amid all these dangers.

We have lost two men from diseases contracted prior to their enlistment.

The health of the command is good.

Of the conduct of nearly every officer and man during these perils, more trying and disheartening than the perils of any battle could be, I cannot speak too highly.

I am, General, very respectfully, your obedient servant,

BENJ. F. BUTLER,

Major-General.

[Indorsement.]

HEADQUARTERS ARMY OF THE POTOMAC,
Seminary, March 22, 1862.

Respectfully forwarded to the Adjutant-General.

By command of Major-General McClellan:

S. WILLIAMS,

Assistant Adjutant-General.

[Inclosure No.l] Itinerary kept by Joe. M. Bell, major and aide-de-camp, at the order of Major-General Butler, U. S. Army.

On the morning of the 25th February the steamer Mississippi, having on board Major-General Butler, with his staff, and the Thirty-first Regiment Massachusetts Volunteers, under Colonel O. P. Gooding, and four companies of the Thirteenth Regiment Maine Volunteers, under Colonel Neal Dow, left Hampton Roads, with fair weather and every prospect of a pleasant voyage, for Ship Island, with intent to stop at Hatteras Inlet, to take on board Brigadier General Thomas Williams, assigned to General Butler, and at Key West. The run through the night was very pleasant, the motion of the ship being scarcely perceptible, the vessel making from 8 to 10 miles per hour.