In some of these clips these technologies are using free energy. The so called Zeppelin was a free energy flying blimp that wasn't a bad invention, rather the robber barons planned to make a propaganda and destroy one of the zeppelins to scare the people, and that's how they ended the age of the zeppelins.
You can also see levitation technology, electric and water engine vehicles in this video. all of this is possible but it was hidden from us.