Among the gravestones at the Fort Lincoln Cemetery, just over the District line in Brentwood, Md., is one marking the final resting place of James Percy Ault : born 1881, died 1929. Ault was, the marker notes, “Cmdr. of the Carnegie.” 

Answer Man prefers a different title: magnetician.

Like the researchers Answer Man wrote about in this space last week, J.P. Ault worked for the Carnegie Institution for Science off Broad Branch Road in the District’s Northwest. While those other scientists plumbed the mysteries of the atom, Ault studied the invisible magnetic forces that enshroud our planet.

He did this by captaining one of the oddest ships ever to sail the seas. Tragically, his life ended aboard it.

Ault and his colleagues in the institution’s Department of Terrestrial Magnetism studied a vexing problem: The north that a compass points toward usually isn’t true north. If you don’t know the exact variation between what your compass reads and what it should read, you’ll have trouble figuring out exactly where you are. Over the course of a sea journey, these errors can put mariners far off their intended course.

To make accurate charts, Carnegie Institution researchers first chartered a yacht called the Galilee, which sailed from 1905 to 1908. But the iron and steel in the ship affected the researchers’ readings.

Louis A. Bauer, Carnegie’s director, suggested a new kind of vessel: a ship virtually free of ferrous metal. And thus was born the Carnegie, a “nonmagnetic” ship constructed at the Tebo Yacht Basin in Brooklyn, N.Y., and launched in 1909.

The Carnegie’s hull was wood. So were many of the nails holding her together: spikes of hard locust. Other fasteners were bronze or copper. So was the stove and most of the engine, which was powered by gas produced from coal, though most of the motive power came from the 12,900 square feet of sail.

The anchors were bronze and lowered not on chains but on lines made from thick hemp. The crew of 25 ate with silver cutlery.

“The sailors may not carry jackknives nor are observers permitted to carry about with them any iron or steel,” wrote the New York Times. “Steel belt buckles, for instance, are taboo. Some wit has gone so far even as to say that a man with an iron constitution is not allowed aboard.”

The Carnegie was 155 feet long and weighed 246 tons. That included a negligible 600 pounds of iron and steel. Ironically, a boat funded by a steel magnate — Andrew Carnegie — had as little steel as possible.

“The ship itself was kind of like the space shuttle of its time,” the Carnegie Institution’s Shaun Hardy told Answer Man.

When the Carnegie paid a visit to Hamburg, 3,000 people were waiting at the dock to welcome it and take a tour.

The Carnegie was at sea for years at a time. On its seven voyages, it covered nearly 300,000 miles crisscrossing the oceans.

Its crew took regular measurements with finely calibrated compasses. The readings were entered in logbooks. Copies were sealed in buoyant, waterproof barrels that were marked with instructions to forward them to the nearest U.S. Consulate. The barrels were then dropped in shipping lanes with the expectation they’d be picked up by passing vessels.

“That’s how they transmitted the data back to Washington,” Hardy said.

On May 1, 1928, the Carnegie left its berth at Washington’s harbor for what would turn out to be its final voyage. The ship had been extensively refitted, an operation that included swapping out its old engine for a new one that ran not on coal gas, but on gasoline.

On Nov. 29, 1929, the Carnegie lay anchored in the harbor of Apia, the largest city on the Pacific Ocean island of Samoa. Ault sat in a deck chair as gasoline was pumped into a holding tank.

A spark ignited fumes in the hold. The explosion blew Ault into the water, killing him and cabin boy Tony Kolar. The Carnegie burned to the water line.

As Ault’s body made its long journey back to Washington, The Washington Post eulogized him: “The record of Capt. Ault and of the Carnegie will not be written in water, but in something more enduring, as science and mankind in general learn to appreciate what they have done to add to the knowledge of the world.”

Questions, please

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