3. Battery Hays, in rear and on the left of Battery Reynolds, comprising nine 30 and four 20-pounder Parrott rifles.

4. Battery O'Rorke, in rear of the right of Battery Hays, comprising five 10-inch siege mortars.

Captain Langdon, First U. S. Artillery, is assigned to the command of Batteries Reynolds and Weed. Lieutenant-Colonel Jackson, assistant inspector-general, with Major Bailey, Third Rhode Island Artillery, as assistance, is assigned to the command of Batteries Hays and O'Rorke. These batteries will be opened upon Fort Wagner immediately after break of day to-morrow. The firing must be executed with great care and deliberation, the object of the rifled guns being principally to dismount the enemy's guns. They will not expend ammunition when their view of the enemy's works is obstructed by smoke. Both time-fuse and percussion shell will be used, preferably the former. Each mortar will fire once every five minutes, alternating from the right in each battery. The shells should be exploded in or directly over Fort Wagner.

By order of Brigadier General Q. A. Gillmore:

ED. W. SMITH,

Assistant Adjutant-General.

79. The distance of these batteries from Fort Wagner were as follows: Battery Reynolds, 1,330 yards; Battery Weed, 1,460 yards; Battery Hays, 1,830 yards, and Battery O'Rorke, 1,920 yards.

Subsequently to this period and through all the most important operations of the season, the commanding general performed the duties of chief engineer. Colonel J. W. Turner was made chief of artillery in addition to his duties as chief of staff. Surg. H. R. Writz became medical director; and Captain Alfred Mordecai, chief of ordnance. Colonel E. W. Serrell, First New York Volunteer Engineers; Captain (now Major) T. B. Books, aide-de-camp; and Lieutenants Suter and Michie, U. S. Engineers, were appointed assistant engineers.

Captain [Chauncey B.] Reese joined the command a few days before the fall of Fort Wagner, and was appointed assistant and consulting engineer.

Characteristic physical features of Morris Island.

80. Morris Island is about 3 3/4 miles long. Its width above height water mark varies between very wide limits (25 to 1,000 yards), while its area is 400 acres, approximately.

81. The center of the island lies in a southeasterly direction from Charleston City, and is 5 3/8 miles distant from it.

82. Cumming's Point, the northern extremity, is exactly 6,616 yards distant from the nearest point of the city, and 2,700 yards distant by the shortest line from Fort Moultrie, on Sullivan's Island. Fort Sumter is 1,390 yards distant from Cumming's Point.

83. Morris Island is widest at its southern extremity, where it is made up of a succession of irregular sand hills and ridges, the highest of which rise to a uniform height of 36 feet above ordinary high-water level, while just south of Wagner the width is reduced to 25 yards and the debts to 2 feet. At this point the sea frequently breaks entirely over the island during the spring tides. On the east side it is gradually yielding to the encroachments of the sea.

84. During the first fifty days of our occupation, the loss in many place was 1 foot per day, while between Fort Wagner and the Beacon House 75 yards in width have been lost since the last charts by the U. S. Coast Survey were prepared.

85. The stratum of mud, of which the salt-marsh which separates James and Morris Islands is composed, passes under the latter and