On the morning of March 9, 1862, the Confederate ironclad Merrimack steamed out to finish the job of destroying the Federal fleet at Hampton Roads, which she had begun with devastating efficiency the evening before. This time, though, the Rebels found something new added to the equation. During the night, the little Monitor had joined her all-but-helpless sisters. The two ironclads fought hull to hull for hours, and at the end the Union squadron was saved, and the two-thousand-year reign of the wooden warship was done.

Most anyone connected with the Brooklyn Navy Yard will tell you that the Monitor was built right there, in Drydock Number 1. It isn’t true—the epochal ironclad was fitted out at the yard but built up the East River in Greenpoint. Nevertheless, it should be true. The Brooklyn Navy Yard is as central as the Monitor to America’s maritime history.

It doesn’t belong to the Navy any more. In 1966, after 166 years of ownership, the government sold the 265-acre complex to the city of New York for twenty-two million dollars. The slips that had sent carriers and battlewagons to the end of the world would be given over to local industries. This might seem a little like cobblers and innkeeps carrying on their business in the vast marble ruins of Imperial Rome, but the project is going well.

“We’ve got a hundred fifty, hundred sixty businesses here now,” says Lee Ader. “They make Sweet ’n Low here—you know, the little pink packages—and cement, lots of stuff.” Ader, a retired New York City fire fighter, has for the last nine years been the fire inspector for the Brooklyn Navy Yard Development Corporation, and he finds his way effortlessly around the scores of buildings that make up the yard. It is an early spring day, dazingly soft and sunny after a week of fog and cold rain, and we are going south across the yard. The towers of Manhattan are right across the river, and it is dislocating to see them standing so close in to all this quiet industrial space.

The place does not make you think of Sweet ’n Low. High on their stilts stand the cranes that lifted the guns into the Iowa and the Missouri during World War II, when the yard was working seventy thousand employees day and night; nearby are long brick sheds where parts were turned for the last of the monitors. Here in this broad inlet shipwrights fitted out more than one hundred vessels for the War of 1812, built the immense seventy-four-gun ship of the line Ohio in 1820, and, in 1837, gave the Navy its first steam warship to be assigned sea duty, the sidewheeler Fulton .

“Here we are,” says Ader. “Drydock Number One.” White spume rises from a pit in the ground, and the air is full of grit. Down in the dry dock teams of men are working on the hull of a coal barge. The workaday craft looks particularly dowdy in this setting, for Drydock Number One is as handsome as anything built in the first half of the nineteenth century. In 1841 the Navy decided to build a dry dock—its first, as well as New York’s. The dock would accommodate a vessel 320 feet long, with a 49.5-foot beam and 21-foot draft.

It would be a permanent structure, to say the least: Master of Masonry Thornton MacNess Niven, who supervised the job, was working with great blocks of granite floated down from the state of Maine and laid on a cement and flagstone foundation. The job was one of the greatest structural achievements of its day—an early-nineteenth-century equivalent to Brooklyn’s other, far better known engineering triumph, its bridge—and it took ten years and three million dollars to complete.

When the dry dock was finished in 1851, a reporter wrote that “no modern structure compares with this national work in the dimensions, or the durability of the materials…, or the beauty and accuracy of their workmanship.” It has never needed major repairs.

Of course, the machinery that attends it has been replaced over the years. The caisson at its mouth dates from the 1920s; when water is pumped in, it sinks to let the sea into the dock and a vessel in or out. If the vessel is coming in, water must be pumped out; emptying the 610,000-gallon stone tub takes more than two hours. “It shocked me at first,” says Ader, “to see all the gulls come flocking around whenever the dry dock was being used.” It took him a while to realize they were there for the easy pickings of fish stranded on the granite floor.

The smoothly joined tiers of granite still convey the same massive and serene authority Niven and his stonemasons imparted to them one hundred and forty years ago. “I took some Japanese businessmen by here a while ago,” says Ader. “They were looking for space to assemble the Metro-North railroad cars they’re making in Japan now. You could see them looking around and thinking: This is how you beat us.”