We can also spare General Augur as soon as we get all the troops under way. At this moment he is most useful in organizing and getting them off. I have sent some 500 railroad operators and General [Benham] to Belle Plain to construct wharves and repair roads to Fredericksburg; there is much delay now in landing troops and stores. Transport are also short, but more have been ordered from Butler. I have sent all dismounted cavalrymen to by Belle Plain as guards for prisoners of war. All Invalids are sent down for same purpose, and to guard depot and trains. The moment a militia regiment reaches Baltimore, Porter's heavy artillery, armed as infantry, will be sent to the front.

I ordered everything beyond Bull Run to be brought in, and the Irish Brigade to go to Belle Plain. General Abercrombie has been ordered to proceed in charge of that depot, with orders to push forward the troops and stores with all possible dispatch. I estimate that we shall have sent forward by Sunday night about 15,000 men - 3,000 to Butler and 12,000 to Army of the Potomac. Possibly I may be able to collect more. You may be assured that no effort will be spared to re-enforce you. You have had some experience in this way before.

Nothing of importance from Butler or Sherman for the last two days. The former was strengthening his position and the latter was moving. * * * McPherson found Resaca too strongly fortified to attempt a coup de main. I wrote you yesterday most of the foregoing details, but you may receive this first. Your dispatch of the 7th did not reach me till this morning, being telegraphed from alexandria. Perhaps it may be well to ascertain what the messenger was doing the intermediate time. I need not say how great is the general satisfaction at your success.

Yours, truly,

H. W. HALLECK,

Major-General and Chief of Staff.

HEADQUARTERS OF THE ARMY,
Washington, May 13, 1864.

Lieutenant-General GRANT:

GENERAL: Since writing to you this afternoon I have obtained detailed reports of troops forwarded and to be forwarded by to-morrow evening to you and General Butler, viz:

Gone:

Recruits, veterans, &c., Army of the Potomac............... 4,300

Mounted Rifles, as infantry................................ 1,000

12th U. S. Infantry........................................ 80

Warner's artillery, as infantry............................ 1,550

Cavalry detachments, remounted............................ 1,500

Regiments from Sandusky.................................... 1,250

107th Pennsylvania Volunteers.............................. 280

67th Pennsylvania Volunteers............................... 250

Under orders:

8th New York Artillery, as infantry........................ 1,800

Irish Brigade.............................................. 2,000

Morris' artillery, as infantry............................. 1,800

Chaplin's artillery, as infantry........................... 1,800

Whister's artillery, as infantry........................... 1,700

turner's [Tannatt's] artillery, as infantry................ 1,700

21,000