There's submicron. Then there's just sub. As in submarine. Such as the naval legend that Rosemount Analytical is helping to preserve in a large tank in South Carolina.

The California-based supplier is providing sensors and analyzers for the restoration of the H.L. Hunley, a Confederate Navy submarine that sunk in 1864 off the coast of South Carolina. The Civil War vessel has a star-crossed history. Built in 1863, the craft sunk twice during testing with all hands aboard before sinking for a third and final time while returning from its only mission. The submarine was recovered in August 2000 by Friends of the Hunley, a nonprofit organization dedicated to honoring the dead seamen and eventually displaying their vessel in Charleston Museum.

Rosemount's instruments track pH, oxygen reduction potential, conductivity, and dissolved oxygen in the storage tank. The second part of the two-phase project involves removing chlorides to prevent corrosion. The large tank is filled with an electrolyte solution to draw the chlorides out of the metal.

Robert Neyland, the project director, says the data from the sensors enable his team to maintain the proper tank environment. Rosemount says the nonprofit organization and its project partners wanted the sensors because of their ruggedness and long life—attributes in marked contrast to the capabilities of the ill-fated war relic.