COLON, Panama (Reuters) — Conserving the world's heritage can take many forms. For Panama Canal tool shop boss Helio Alves, it has meant putting two gallons of lake water under lock and key in his office safe.

Alves is responsible for safeguarding a fragile relic that turned up last month when salvage workers raised an abandoned French locomotive and 15 cars from the Panama Canal.

The mud-caked rolling stock, dating from a doomed French bid to forge a path between the seas in the 1880s, was lost when U.S. engineers successfully flooded the waterway in 1914.

Hailed as "a gem . . . a real treasure" by Canal Minister Ricardo Martinelli as it emerged from 45 feet of water in Lake Gatun on May 15, the steam engine now rests on a concrete apron overlooking the Caribbean entrance to the canal it helped to build.

To avoid accelerating corrosion by exposure to the damp tropical air, Alves and his team have put cast-iron plaques from the engine and wagons in shallow trays of water for safekeeping while authorities decide how to conserve them.

"It's like guarding a mummy," the official said as he fished a series of heavily corroded "Societe Anonyme Franco Belge" nameplates from the mineral-rich soup.

"We're keeping them in lake water while we wait for the experts."

Covered in a deep crust of rust and clamshells after 85 years at the bottom of the canal, the French-era locomotive presents a conservation riddle for the Panama Canal Authority.

So far PCA authorities have consulted with the locally based Panama Canal Museum and National Cultural Institute and have been contacted by researchers at the Smithsonian Institute in Washington.

The find sparked considerable international interest and has attracted suggestions from researchers as far away as Australia and from one paint manufacturer from the U.S. While the PCA waits for guidance and a political decision on how best to display the engine, it has blasted away mud and rust caking three of the cars to reveal the original metal.