On the 30th I ordered all the cavalry then available forward, under Major [H.] Robinson, to disperse the rebel cavalry, reported on the left bank of the Bayou Boeuff. He fund his force inadequate to the purpose. Yesterday all the cavalry, including the Fourth Wisconsin, which had now arrived rom its exclusion on the palings to the west, was ordered forward, under the command of Brigadier-General Dwight, with orders to attack, and, if possible, disperse this same cavalry of the enemy. Brigadier-General Dwight's report has already beans sent you.

Grave disorders in our rear by bands of robbers, sometimes headed by stragglers from the ranks, which threatened for a moment to interrupt our communication, and even to disband and sippers into a band of robbers and thieves some of our loss disciplined regiments, induced me to publish a short notice, which I have the honor to show you. In this same connection I think proper to state that I sent ten men of the Fourth Wisconsin to the village of Grand Coteau to arrest and drive in stragglers and to preserve order. The inducements for plunder in this country are so great that unless high-handed measures are taken many men will be lost to the ranks ont he day of battle.

When I received the reports of the enemy's being re-enforced by Generals Smith and magruder, as a recautionary measure I ordered the two regiments sent with cattle to Brashear City to return from that place as soon as they had delivered their cattle and re-enforced the garrison at New Iberia.

The staff of the general commanding having been left behind, every order issued has been through them, and you will find at the headquarters of the Nineteenth Army Corps, the record of every movements and transaction since you left here.

I have the honor to be, respectfully, your obedient servant,

W. H. EMORY,

Brigadier-General, Commanding.

Lieutenant Col. RICHARD B. IRWIN.

P. S.-I have omitted to mention that on April 30 Brigadier-General Grover was directed to send an infantry force in skiffs to search the creeks leading into the Bayou Curtableau. No report is yet received from him.

No. 10. Report of Captain Richard C. Duryea, First U. S. Artillery, Chief of Artillery, of engagement at Fort Bisland and skirmish at generate.

CAMP AT OPELOUSAS, LA.,

April 20, 1863.

SIR: In compliance with instructions I have the honor to submit the following report of the operations of the batteries of the Third Division during the 12th, 13th, and 14th instant:

On the 12th instant a section of the First Maine Battery, under command of Lieutenant Morton, was sent across the Bayou Teche, engaging a rebel battery until ordered to withdraw.

On the following morning the other two sections of same battery were sent across with Colonel Gooding's brigade, and, having joined Lieutenant Morton, engaged a rebel battery in the open field, and after an hour's contest drove them behind their breastworks. Lieutenant Haley