From: Dictionary of American Fighting Ships, Vol. III, 1968, Navy  

Department, Office of the Chief of Naval Operations, Naval History  

Division, Washington, D.C. 

 

IOSCO 

 

SwStr: 

t. 974; 

l. 205'; 

b. 35'; 

dph. 11' 6"; 

s. 9 k.; 

cpl. 173; 

a. 2 100-pdr. Pr. 4 9" D. sb. 2 24-pdr. how., 1 heavy 12-pdr., 1 12-pdr. 

 

IOSCO, a wooden double-ended, side-wheel gunboat, was launched by 

Larrabee & Allen, Bath, Maine, 20 March 1863; and commissioned at the 

Boston Navy Yard 26 April 1864, Comdr. A. J. Drake in command. 

 

She was at New London, Conn., 9 June when ordered to New York to 

complete her crew. 

 

IOSCO sailed for the Gulf of St. Lawrence 28 August to protect American 

fishing vessels in that vicinity. Off Nova Scotia and Prince Edward 

Island, she assisted several ships endangered by fierce storms. She 

towed GENERAL BURNSIDE off a reef 15 September and aided battered 

COLONEL ELLSWORTH and the English Bark EMPRESS 2 days later. 

 

Ordered to Hampton Roads 2 October to join the 1st Division of the North 

Atlantic Blockading Squadron, IOSCO was stationed off Wilmington, where 

she captured British schooner SYBIL attempting to escape to sea with 307 

bales of cotton 21 November. 

 

On Christmas Eve 1864, IOSCO participated in the first amphibious attack 

on Fort Fisher, N.C. which protected Wilmington, one of the South's most 

active centers of blockade running and her last port of entry for 

European aid. Her guns engaged the batteries at Mound Fort and succeeded 

in shooting down the Confederate flay which flew above the works. During 

the firing a Confederate shot carried away the head of IOSCO's foremast. 

The next day, she led nine other ships in an attack on the fortress, 

closing the shore as near as her draft would permit. Meanwhile her boats 

dragged the channel for torpedoes. Throughout the operation she 

protected the right flank of the Union troops ashore until they 

reembarked under orders from the Army commander, Major General B. F. 

Butler 27 December 1864. 

 

A fortnight later IOSCO was again in the thick of the fighting during 

the second attack on Fort Fisher. She assisted the landing of troops and 

covered the right flank of the Army as it fought on shore 13 January 

1865. Forty-four of her own men fought beside the soldiers on the 

beaches while her cannon fired at the mound until the Confederates 

surrendered 15 January. 

 

The remainder of IOSCO's wartime service was in the North Carolina 

Sounds carrying out operations as Confederate resistance ceased. She 

sailed north 15 July and decommissioned 28 July 1865. Her engines were 

removed and her hull turned over to the Bureau of Construction and 

Repair for service as a coal hulk at the New York Navy Yard in February 

1868.