20,000 Leagues Under the Sea - 1916

From Wikipedia: https://en.wikipedia.org/wiki/20,000_Leagues_Under_the_Sea_(1916_film)
20,000 Leagues Under the Sea is a 1916 American silent film directed by Stuart Paton. The film's storyline is based on the novel Twenty Thousand Leagues Under the Sea by Jules Verne. It also incorporates elements from Verne's The Mysterious Island.

This was the first motion picture filmed underwater. Actual underwater cameras were not used, but a system of watertight tubes and mirrors allowed the camera to shoot reflected images of underwater scenes staged in shallow sunlit waters.

The film was made by The Universal Film Manufacturing Company (now Universal Pictures), not then known as a major motion picture studio. Yet in 1916, they financed this film's innovative special effects, location photography, large sets, exotic costumes, sailing ships, and full-size navigable mock-up of the surfaced submarine Nautilus. Hal Erickson has said that "the cost of this film was so astronomical that it could not possibly post a profit, putting the kibosh on any subsequent Verne adaptations for the next 12 years"