Merrimac, less often reported as Merrimack, was one of the original group of Confederate Government-owned blockade-runners operated by the Ordnance Department, CSA (cf. Cornubia). She was an iron paddle-steamer with two stacks "hinged for lowering," a short foremast only, which could be bark-rigged, and was said to have done 18 knots on her trials. Her pair of 9-ft. stroke, oscillating sidewheel engines and 4 boilers were considered "very superior and valuable" until her flues became clogged by burning naval stores in emergencies -as so often happened in this dangerous service. It is said Merrimac was built for opium running on the China coast.
Apparently she was bought for the Confederacy by Commissioner James M. Mason and N. S. Reneau in or before September 1862. By the time of her capture by USS Iroquois 24 July 1863 off Cape Fear she had lost her speed and been sold with her cargo to new owners- one of whom, a Mr. Roberts, was taken in her-for $2,200,000 Confederate. She was loaded deeper than prudence directed for running the blockade, with 642 bales of cotton plus turpentine and tobacco.
