Dolphins, known to be the most intelligent among sea creatures, were being trained by the United States Navy to search for sea mines and illegal divers. However, instead of sea mines, they recently uncovered a 150-year old piece of American history.

An early naval torpedo was discovered deep in the ocean by two Navy dolphins in the coast of Coronado, California. According to the Los Angeles Times, it may have failed to detonate 150 years ago.

"Dolphins naturally possess the most sophisticated sonar known to man," the U.S. Navy Marine Mammal Program's website explains. Using animals "can effectively replace a full-sized naval vessel and its crew, a group of human divers, and the doctors and machinery necessary to support the divers operating onboard the vessel."

The U.S. Navy Marine Mammal Program, a program governed by the U.S Navy which uses marine animals for naval operations, preferred to invest on marine animals such as the dolphins, sea lions and whales instead of mine-hunting machines because they do the same task well with fewer security risks.

Critics complain about the program endangering these marine animals because of the active mines but it remains adamant that the dolphins are very unlikely to cause explosion because of its weight and speed.
The U.S Navy denied that they were training the dolphins for combat operations even if there were rumors that there are existing combat-trained dolphins.

"Several decades of classification of the program's true missions … [led to] speculation and charges that could not be countered with facts due that classification," the website explains. "Additionally, fantasy is often times more interesting than reality."

The Howell Automobile torpedo that the dolphins found was the first locomotive torpedo made by the U.S Navy in 1870. Only 50 of it were produced during the time and it was the 24th which the dolphins found.

Historians are now investigating how the torpedo ended up at the bottom of the Pacific Ocean.