Daniel Ammen, Confederate Military History, a library of Confederate States Military History: Volume 7.2, The Atlantic Coast
Clement Anselm Evans, Ed.

Admiral Dahlgren, upon assuming command, had shown him by Dupont a letter from Gillmore, to the effect that lie was about operating on Morris Island, and asked naval cooperation. This had been declined in order to enable his successor to make all preliminary arrangements.

‘General Gillmore had informed him [Dahlgren] that the enemy appeared to be aware of his design, and was working on Morris Island with great activity to defeat it, and would succeed unless speedy action was taken. There being no time to ascertain the views of the Department it only remained for him to furnish the assistance required.’

This he proposed to do with the monitors, with what assistance from the wooden vessels was found practicable. He regretted the probability that at the time desired the Ironsides would not be able to cross the bar. He says: ‘Of course, the most that is expected from the action of these vessels is to relieve the troops as much as possible, and is to be considered of no other consequence.’

On the 10th of July General Gillmore opened his batteries, situated on the north end of Folly Island, against those of the enemy occupying the southern sand-hills of Morris Island.

At 4 A. M. the Catskill, Commander George W. Rodgers, the Montauk, Commander D. M. Fairfax, the Nahant, Commander John Downes, and the Weehawken, Commander E. R. Colhoun, passed the bar, the admiral's flag being on board of the leading vessel. General Gillmore opened fire about this time, and as soon as sufficiently near, the monitors opened fire with shell upon the enemy's batteries, which were replying to those of General Gillmore. The fire of the monitors dispersed the enemy wherever seen to assemble. About eight o'clock the land batteries ceased firing and the troops in some force were seen making their way along the beach on Morris Island.