The anti-gravity house is actually built at an angle of 25° off the true horizontal. This will explain every effect seen. Once in the area of an anti-gravity house you are always comparing the effects to what you are used to -- normal-level floors and walls that are perpendicular to the ground.
The Leaning Off Walls Effect
On the left-top diagram you see the actual tilt of the house to the true horizontal.
Both people are perpendicular to the true horizontal. On the left-bottom, you see the situation as it is perceived by the people inside the room.
They have no access to the true horizontal, and are judging their surroundings by a horizontal that is created by the room. This causes one to have an internal change of reference frames, which causes the people to appear as they are actually leaning off the walls.
Clinging Objects Effect
The same reason as above accounts for this mysterious phenomena. In the middle-top diagram you can see that the Earth's gravity fully holds the chair against the wall. However, to the observer inside the room, the chair appears to mysteriously stay against the wall.
Objects Rolling/Water Flowing Uphill
On the right-top diagram, the board or trough is at a very slight downhill incline from the true horizontal (about 5 to 7 degrees). On the right-bottom, you can see how the effect appears to the observer. The house is tilted at an angle of 25 degrees. Someone inside the house perceives the upwards incline of the ramp to be 20 degrees, which is a pretty dramatic incline!
History of Anti-gravity Houses
Many of these tourist attractions have claimed to be the original site where this effect was first discovered. A little research on their chronology has allowed us to determine who plagiarized from whom. The House of Mystery in the Oregon Vortex, Gold Hill, Oregon was the first one built. It was first constructed during the 1930's, as an attraction during the Great Depression. The attraction proved popular enough to have imitators, and other anti-gravity houses started appearing, each identical in construction, appearance, and presentation of effects. This, of course, started lawsuits between the various owners.
Even the legends surrounding the anti-gravity houses are identical. For example, the building accidentally slid down the side of the mountain, coming to rest against the trees, which accounts for its strange tilt, and then the owner noticed strange and weird effects, but only within that local area. Almost all of the tour guides state that the effects are due to strange phenomena in the area, magnetic anomalies and the like.
There are quite a number of these anti-gravity places around the United States. They are well worth the visit! Here is a map.
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