HEADQUARTERS DEFENSES OF NEW ORLEANS, July 13, 1863.

Brigadier-General GROVER,
Donaldsonville:

Supposing a movement had been commenced down the La Fourche, I sent what little available force I have forward on the railroad to reconstruct the railroad bridges, so as to be able to supply the troops by rail when they reach La Fourche Crossing, and at the same time make a diversion in your favor; but the moment they pass Boutte Station they are liable to be cut off, unless acting in co-operation with the force Donaldsonville down the La Fourche. Therefore, I request you will inform me when the movement takes place.

The enemy are in very considerable force.

Respectfully, your obedient servant,

W. H. EMORY,

Brigadier-General, Commanding.

HEADQUARTERS DEFENSES OF NEW ORLEANS, July 13, 1863.

Lieutenant-Colonel IRWIN,
Assistant Adjutant-General, Port Hudson:

The Cromwell is in, with dates to the 4th, and the latest news we have from Gettysburg, July 3,1 p. m., Meade had driven the enemy 4 miles north and west. Meade appeared to be driving the rebels. Longstreet reported killed. Jeff. Davis reported at Greencastle, Pa. Richmond closely invested by General Dix.

The news in their vicinity:The rebels are withdrawing from my front on the west bank. I have sent forward Stickney, with 300 infantry and all the cavalry, to press toward La Fourche, and reconstruct the bridges on the Opelousas Railroad.

W. H. EMORY,

Brigadier-General, Commanding.

HEADQUARTERS DEFENSES OF NEW ORLEANS, July 13, 1863.

Lieutenant-Colonel IRWIN,
Assistant Adjutant-General, Port Hudson:

The lines made for the defense of this city were planned for the river at the flood and the marshes full of water. Now that the river is fallen and the marches dry, these lines could have been turned in a number of places.

We have a force of at least 1,000 men repairing these defects, under Acting Brigadier-General Houston.

Although the emergency is passed which caused me to commence the work, it is my opinion, and General Houston's also, that we should go on and complete it, and also make an inclosed work which shall command the city independent of the navy. Shall we go on?

W. H. EMORY,

Brigadier-General, Commanding.