After the removal of the Wall's Cut obstructions a joint expedition of land and naval forces for the investment was organized by General Sherman and Commodore DuPont. This expedition consisted of one regiment of infantry (the Forty-eighth New York Volunteers), two companies of the New York Volunteer Engineers, and two companies of the Third Rhode Island Volunteer Heavy Artillery, with 20 guns of all caliber, viz, two 8-inch siege howitzers, four 30-pounders Parrotts, three 20-pounder Parrotts, three 12-pounder James rifles, and eight 24-pounder field howitzers, and was accompanied by three gunboats. The troops were to rendezvous at Daufuskie Island, where we already had three companies of the Seventh Connecticut Volunteers, under Major Gardiner, guarding Wall's Cut. They had been posted there on January 13. The land force was in readiness at Hilton Head soon after the middle of January. Various causes delayed the expected naval co-operation, so that no gunboats passed Wall's Cut until the 28th of January. The naval forces were commanded by Commander John Rodgers, U. S. N.; the land forces by Brigadier-General Viele. Another mixed force, approaching by way of Warsaw Sound, presented itself on the south of the Savannah River, in Wilmington Narrows (or Freeborn's Cut), at the same time, the land force being commanded by Brigadier General H. G. Wright and the gunboats by Fleet Captain Davis.
On the afternoon of January 28 a reconnaissance was made by me of Mud River and the Savannah River shore of Jones Island. Venus Point, on the margin of the Savannah, was selected as the position for one of the investing batteries. The line for a road or causeway over the marsh between Venus Point and Mud River was also located. Its length was nearly 1,300 yards. This causeway or corduroy was never completed.
Jones Island is nothing but a mud marsh, covered with reeds and tall grass. The general surface is about on the level of ordinary high tide. There are a few spots of limited area, Venus Point being one of them, that are submerged only by spring tides or by ordinary high tides favored by the wind, but the character of the soil is the same over the whole island. It is a soft unctuous mud, free of grit or sand, and is incapable of supporting a heavy weight. Even in the most elevated places the partially dry crust is but 3 or 4 inches in depth, the substratum being a semi-fluid mud, which is agitated like jelly by the falling of even small bodies upon it, like the jumping of men or ramming of earth. A pole or an oar can be forced into it with ease to the depth of 12 or 15 feet. In most places the resistance diminishes with increase of penetration. Men walking over it are partially sustained by the roots of reeds and grass, and sink in only 5 or 6 inches. When this top support gives way they go down from 2 to 2 1/2 feet, and in some places much farther. A road or causeway of some kind across Jones Island from Mud River to Venus Point was deemed necessary and determined upon at the outset, even if the guns should not have to be carried over it, as the means of getting speedy succor to the Veenus Point battery in case of attack; Daufuskie Island, 4 miles distant, being the nearest point where troops could be kept for that purpose.
On thee 29th of January Lieutenant O'Rorke, of the Engineers, was dispatched by me in a small boat to examine Long and Elba Islands, in the Savannah River. Major Beard, Forty-eighth New York Volunteers, accompanied him. They entered the Savannah River via Cunnigham Point at the lower end of Jones Island, pulled up the Savannah, stopping several times on Long and Elba Islands, and west around the west end of the latter to within about 2 miles of Fort Jackson. Lieutenant