HEADQUARTERS THIRTEENTH ARMY CORPS,
Pass Cavallo, Tex., April 11, 1864.

Lieutenant Colonel RICHARD B. IRWIN,

Asst. Adjt. General, Department of the Gulf:

COLONEL: I have just returned from a tour of inspection and observation, embracing the whole coast of Texas south of this place and the frontier from the mouth of the Rio Grande to Brownsville. I will not dwell on the details affecting the condition of our forces stationed along this extended line, which were lately brought to the attention of the general commanding by Major-General Ord, and which either have been or are in course of being definitely arranged. I pass to other considerations. The health of the troops is good, excepting some cases of ophthalmia, increasing in number and caused by flying sand, and a limited number of other cases such as are incident to camp life. Fatigue duties have been heavy and continuous, consisting of constructing defensive works in shifting sands and unloading boats. The amount of labor bestowed on such works here on Mustang Island and at Brazos Santiago would, from the cause mentioned, have reproduced the same works several times. The works here are nearly completed, except rivetting with sod, which, from the scarcity of such material and of wagons to haul it, has proved to be a tedious job.

In the absence of suitable lumber I have improvised, to the extent of my limited means, temporary platforms for guns for such of the works as are ready to receive them. The works on Mustang Island are of little or no value, not only for want of intelligent and consistent design, but from the difficulty, if not impracticability, of preserving their identity amid the drifting sands. Major Thompson, who is in command on this island, informed me that the location of his camp was fixed at or about the time our forces left there for Fort Esperanza, and that he had not felt at liberty to remove it. The location is immediately among the hand-hills and is almost uninhabitable. Have ordered an examination to be made for the purpose of ascertaining whether the garrison and guns there might not be transferred to a position on the foot of Saint Joseph's Island equally favorable to command Aransas Pass more favorable for a camp; but of course, in view of what has been said, would not order accordingly without the consent of the general commanding.

Major Thompson has scoured the neighboring shores and captured all the enemy's boats, large and small, that he could find. On the night before I arrived at Mustang one of his parties had occupied Corpus Christi and learned that Nolan's rebel company had been infesting that vicinity. Corpus Christi, as I learned at Brownsville, has been since occupied by Ford's command, numbering variously, according to different accounts, from 400 to 700. The work on Brazos Island is misplaced and incapable of commanding the inlet to Laguna del Madre, but a new work has been begun by Colonel Hodge, commanding that post, which, from its plan and location, with proper armament, will be effectual for the purpose. Six guns with barbette carriages were being unloaded there, as I was informed for the works at Brownsville. The route between these two places, via Boca Chica, has superseded the more difficult one via Point Isabel, and thus time and distance have been saved. In view of this fact, I cannot see that any valuable object is to be secured by continuing the present garrison of two companies at Point Isabel, unless it be to

9 R R-VOL XXXIV, PT III