The steamer Saint Mary's passed by the bar yesterday morning, and news reached me at 10 a. m. from her that you had captured the garrison at Aransas Bay. I at once telegraphed to Fort Jackson, and had a telegraphic dispatch, announcing the success to General Halleck, placed on board.

Captain Dunham being convalescent, and recommended to go north by the medical officers, I had sent him on the Washington, charged with duplicates of your dispatches by the last steamer, and a short report on the occurrences of the week to the General-in-Chief and Adjutant-General.

The steamer Corinthian sails to-day, taking two Iowa regiments, 600 men.

The Saint Mary's will be sent to-morrow with about the same number and the transportation. I have ordered the purchase of three prize schooners for running stores to Aransas, and hope to get them off to-day laden with subsistence and ammunition.

I have ordered-have had a standing order with the quartermaster's department to get possession of any steamer and sailing vessels coming into port which can be used, and have dispatched them as fast as procured. The Nathaniel P. Banks was so strained getting around to Brashear that it was not deemed safe to send her to Texas. She will be used between this and Pensacola.

Yesterday I received very direct information that the rebels in Mobile were moving troops to Pollard and Bonsecours Bay, intending to attack Pensacola in both directions. I immediately wrote to General Asboth, warning him, and sent by the steamer George Peabody, which will probably reach him in time to prevent surprise. I have already informed you by the Scott of General Lee's handsome operation in capturing the Sixth Texas (rebel) Cavalry. It was a dashing and successful affair; only 25 escaped. Twelve officers and 100 men were captured. Plaquemine is now well fortified, and secure. Green has undoubtedly affronted [confronted] the Mississippi River, and no doubt intends to occupy a point to blockade the river. If the occupation should be at all serious, I shall send up a force to co-operate with the navy in capturing him. This can be done without interfering with the transportation of troops to your re-enforcement.

I would now recommend raising the embargo on Berwick Bay, as much suffering is caused by it within our lines on the Teche, and, if properly watched, no mischief can result from a judicious granting of passes for proper persons, and supplies to the people. Now we have to feed starving people from the army supplies, who could and would procure for themselves, if permitted. I intend to send, by next opportunity after the Saint Mary's, the Twenty-second Regiment, Corps d'Afrique, to Texas, as Major Houston represents the services of colored regiments much needed there.

NOON, 22d.-Your dispatch of 17th, dated off Aransas Pass, has just been received. I shall at once communicate with Admiral Porter and Commodore Bell on the subject of gunboats for Berwick Bay. If they cannot furnish any, I will make two for that service. I fear we shall have to do this, from the results we have had from former applications.

I have nothing new to communicate from up the river, although the telegraph is working well to Port Hudson, and General Andrews had instructions to report frequently. From this silence, I suppose there has been as yet nothing serious at Morganza.

Very respectfully, I am, general, your most obedient servant,

CHAS. P. STONE,

Brigadier-General, and Chief of Staff.