Longer than Cumberland by half, with a submerged iron ram projecting from its bow, the approaching vessel looked to the Union ship’s pilot like a “huge, half-submerged crocodile.” Virginia tore into Cumberland’s bow below the waterline (see pages [28]-29), then backed off, leaving its ram imbedded in a seven-foot hole. Both vessels now loosed volleys at point-blank range; dozens of Cumberland’s crew were maimed or killed.
As the vessel listed and began to sink, the crew abandoned ship, but 121 men—already dead, too hurt to save themselves, or firing guns to the end—went down with Cumberland. (As water flooded the gun deck, a young gun crew officer barely saved himself by squeezing through a gun-port. He was Lieutenant Thomas Selfridge, who in 1890 became commandant of the Charlestown Navy Yard.) Before darkness ended the fighting, the ironclad also riddled Congress, killing more than a hundred men and setting the vessel on fire. Congress burned on into the night and finally exploded.
The frightening weapon that had handed the U.S. Navy its worst defeat began its career as the hull of a wooden steam vessel. A week after the surrender of Fort Sumter, the loss of the important Gosport Navy Yard at Norfolk to rebel troops became inevitable. Evacuating Union forces—under cover of Cumberland—burned and scuttled several warships to keep them from falling into Confederate hands. But some were salvageable, including a large steam frigate on which everything below the waterline was intact. Southern engineers converted the vessel into an advanced warship, removing the masts and topping the hull with a rooflike iron shell. The original name of the vessel they retrieved and transformed: U.S.S. Merrimack.
Merrimack’s reincarnation as Virginia embodied two technologies—steam and iron (and then steel)—that were advanced during the Civil War and that eventually defined the modern Navy. Steam engineering had traveled a long road of acceptance in the conservative Navy. By 1850, the year the Charlestown Navy Yard built its first steamer, Great Britain had built or converted from sail some 25 propeller and paddlewheel steam warships. The U.S. Navy had launched only seven. Steam engines were still considered novelties by many old Navy men—at best auxiliary power, at worst dirty and undependable nuisances that called for machine tenders rather than sailors.
Their resistance was not entirely unjustified. There was the problem of range: Merrimack, for instance, could cruise only about 17 days with its coal bunker full. American steamers far from home had to depend on French or British coaling stations and machine shops in places like Hong Kong and Shanghai. Unlike self-reliant sail, steam alone could not meet the demands of distant squadrons. And in the early days of steam, it was no faster than sail: in fact it was often slower. More crucial, early steam engines were inefficient and unreliable, so captains would not trust them in combat. And coal took up valuable space needed for supplies, crew, and ammunition.
But the main problem was that early steamers were driven by big, ungainly sidewheels that caused captains no end of problems (see [page 35]). They so harmed a vessel’s sailing qualities that steam was of necessity the primary power source on sidewheelers—but the Navy wanted to use steam only as auxiliary power.
Another way of employing steam power for propulsion was needed. The propeller (called a “screw”) was the answer, allowing naval steam to come into its own. Construction of the prototype screw sloop Princeton began in 1841, before America’s first sidewheel warships even went into service. The Navy built only eight more deepwater sidewheelers before the famous 1854 class of six screw steamers (led by the Charlestown-built Merrimack) made the cumbersome vessels a footnote in naval history. With the advent of the propeller, enough problems were solved that auxiliary steam power became feasible in warships. On an 1858 cruise from Honolulu to Acapulco, Merrimack steamed only three days out of 32.
Merrimack, whose subsequent adventures we have already followed, was in the tradition of large American frigates like Constitution. While its engines were never very dependable, Merrimack was an excellent sailer, powerfully armed, and on its inaugural European cruise inspired Britain to build similar vessels with better engines.
Merrimack is launched at Charlestown in 1855; Cumberland was built in the same shiphouse in 1842.