From the Super Mario Wiki, the Mario encyclopedia
The Levitation Beam is a machine owned by the Koopa Troop that can levitate very large objects. The levitation beam is only ever seen in The Adventures of Super Mario Bros. 3 episode "Reptiles in the Rose Garden", where it is used to lift the White House off the ground so that King Koopa can take it and the President back to Dark Land and allow Kootie Pie Koopa to rule America. He later uses the Levitation Beam to position the White House over the Mushroom Sea and allows it to sink to the bottom.
After Mario raises the White House from the bottom of the sea, he and Luigi sneak on board the Doomship and Mario manages to take control of the beam, using it to warp the White House back to Washington. Although Mario accidentally puts the White House on top of the Washington Monument, he afterward places it back in its proper location. Upon returning the White House, Mario then uses the beam to send Kootie Pie back to Dark Land.