HEADQUARTERS THIRTEENTH ARMY CORPS,
Pass Cavallo, Tex., March 23, 1864

Major-General DANA,

Commanding First Division, Thirteenth Army Corps:

GENERAL: Captain Armstrong, of the scouts, reports, under date of yesterday, that the enemy sent forward a party on the same day to reconnoiter the Oyster Bank Reef, while a larger force remained behind on the mainland for an hour or two, when all withdrew from view. I have sent my cavalry troop down the island this morning to meet any additional information. You will be on the alert to meet and vanquish contingencies.

Your obedient servant,

JOHN A. McCLERNAND,

Major-General, Commanding.

HEADQUARTERS THIRTEENTH ARMY CORPS,
Pass Cavallo, Tex., March 23, 1864

Captain WINGETT,

Commanding Mounted Infantry:

CAPTAIN: You will direct your messengers to report in person to Colonel Bailey, commanding the outposts, as they pass back and forth. It is important that he should be informed early of the slightest appearance of the enemy.

By command of Major General John A. McClernand:

SAMUEL CALDWELL.

Acting Assistant Adjutant-General.

ENGINEER'S OFFICE,

Pass Cavallo, Tex., March 23, 1864

Captain B. WILSON,

Assistant Adjutant-General:

SIR: I have the honor to submit the following report relative to progress made and number of men employed on fortifications at this point: The following regiments were employed on second line on the 21st of March instant:

Men.

34th Iowa Volunteer Infantry.............................. 95

49th Indiana Volunteer Infantry........................... 245

114th Ohio Volunteer Infantry............................. 170

21st Iowa Volunteer Infantry.............................. 260

18th Indiana Volunteer Infantry........................... 120

69th Indiana Volunteer Infantry........................... 275

22nd Iowa Volunteer Infantry............................... 290

23rd Iowa Volunteer Infantry............................... 200

The above regiments were from the First and Second Brigades, First Division, Thirteenth Army Corps. They were worked by reliefs, one-half of each regiment working at the same time. The Twenty-second and Twenty-third Iowa were on the works only half of the day. One hundred men were engaged in making revetments at redoubt on left of the line. The sodding of this work is somewhat difficult, and it can only be prepared to receive the sods as they are