prehending delay, I sent an aide expressly to supply any deficiencies or arrangements that might be necessary to prevent postponement. A copy of the report of the aide is sent herewith. The violent storm that rose last evening and continued so long would certainly have interfered with the success of the operation. This morning I intended that, so far as I was concerned, nothing should interfere, and I sent a tug for one of the lighters to have the powder put in and secured against a storm. In return a message was received from you saying that you would try the experiment from the shore batteries.

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

J. A. DAHLGREN,

Rear-Admiral, Commanding South Atlantic Blockading Squadron.

[Inclosure.]

FLAG-STEAMER PHILADELPHIA, Off Charleston, S. C., July 22, 1864.

Rear-Admiral J. A. DAHLGREN,

Commanding South Atlantic Blockading Squadron:

SIR: In conformity with your instructions, I went on board of the Nahant yesterday evening about 6 to see that everything was ready for the explosion of the powder, and also your order to Captain Mayo "to use his own direction," and that you relied entirely upon his judgment in the execution of the matter. Captain Mayo decided not to go on account of the very bad state of the weather, but he desired to complete the undertaking as soon as the weather would permit. I also delivered your order for Captain Mayo to come down as soon as the explosion was over, in case he should have gone up, and let the regular picket monitor take her station for the night. On my return to the flag-ship, I gave a passage to Captain Shelton and Acting Ensign Neil to the Cosmopolitan in my boat. From the fact of Captain Mayo deciding not to go, after delivering your order to act at discretion, these officers may have ben led to believe that I brought an order not to make the experiment last night.

Respectfully,

E. J. DICHMAN,

Ensign, U. S. Navy.

HDQRS. DISTRICT OF FLORIDA, DEPT. OF THE SOUTH, Jacksonville, July 22, 1864.

Colonel JAMES SHAW, JR.,
Commanding Seventh U. S. Colored Troops:

COLONEL: The general commanding directs that the following instructions will be observed by you:

First. Embark your command at 3 p. m. to-day.

Second. Go up the river so as to arrive at the gun-boat Hale, at the mouth of Black Creek, at 7 p. m.

Third. Land your troops at the landing indicated by Lieutenant Burton, aide-de-camp, who will get a pilot for one of the boats. The landing is to be made in the quickest possible time from each boat, and each boat, as soon as emptied, will return at quick speed to Mandarin to bring up the Seventy-fifth Ohio Volunteers with their horses.