I was aware of their service on the Arkansas. In the picture below the 2nd man from the right is private Daniel Black who was one of those that served the guns of the Arkansas with 1st Lt. Robert Mathews. This is RB Mathews' report of the action from the ORs
HEADQUARTERS GRACEY'S [COBB'S] BATTERY,
July 17, 1862.
[Brigadier General W. PRESTON:]
GENERAL: In reply inquires concerning the volunteers from our battery "to assist in fighting the ram Arkansas" against the lower fleet, I report as follows: On the 15th instant, about 4p. m., Lieutenant [H. P.] Wallace, of your staff, came to our battery and stated that you desired 12 volunteers from your brigade to fill the place of the wounded and dead in the crew of the ram. Twelve members of the battery, besides myself, immediately volunteered to go, but our commanding office refusing to permit so many of us to leave, as it would reduce the strength of his battery, resorted to a ballot to see who the lucky ones might be, which resulted as follows: Sergt. James Bridndley, Corpl. John Leonard, Privates Benjamin [G.] Moore, Daniel Black, and Charley Thronton, and Sergt. T. Watts. As soon as the volunteers were ready to move, which was about five minutes after, I took the men and reported myself and command to Captain Brown, of the ram, as being a portion of the number required of your brigade. Captain Brown immediately assigned us to a gun. I stated to Captain Brown that we had come to assist him to fight the lower fleet that evening, and that we had come to assist him to fight the lower fleet that evening, and that as my whole experience in artillery was confined to light fieled pieces, except what I had learned from the morning engagement with the enemy's boats, would prefer that he would place some officer in charge that had more experience, and I would fight as a private, which was done, as he placed Midshipman [D. M.] Scales in charge. We worked the gun throughout the engagement to the best of our abilities. After the engagement was over, I asked the first lieutenant if they needed our services any more. he conducted me to Captain brown, who stated that he had no further use for us, and that he was very grateful for our services, and that we could return to our camp. I asked him then for the countersign; he did not have it. I asked General Breckinridge's son for it, who was standing by during my conversation with Captain Brown; he not having it, was compelled to remain in town until morning, when we returned to our battery. These are all the circumstances connected with our aquatic expedition, and trust that they are of such a character as will relieve your mind of any impression you may have received of myself or any of those under my command acting in any way except at Kentuckians have always and will continue to act before the enemy, whether on land or water.
I am, sir, very respectfully, your most obedient servant,
R. B. MATHEWS,
First Lieutenant Cobb's Battery.