Ecuador equator myth of draining water

In Quito my friend and I visited the (ofcourse we did, we like to play the happy tourist too) Equator monument standing over the imaginary equator line. Mitad del Mundo was constructed between 1979 and 1982 and is about 27 km from Quito. The more than briljant bus sytem brought us all the way to the city limit, changing bus to a smaller villages just outside Quito. First the official monument, where tons of tourists run around the monument to be in the so-called north and south hemispheres. "So-called" because it`s not truly on the equator line. About 240 meters off according to GPS.

Next we went to the Inti Ñan museum. They claim to be on the true equator line and offer good English speaking guides included in the 3 dollar entrence fee (Ecuador uses USD). The most intriguing part about this small private musuem is that they have and show "scientific experiments" that proof that they are exactly on the right spot.

One of the experiments is the well known water draining effect above and below of the equator. North counter-clockwise, South clockwise, and exactly on the equator (and only there) straight down. Complete bullocks, will any google (or wiki) search tell you. But they tried to keep that common misconception standing to "proof" their equator line is the true and only one.

The experiment involved a sink on a table frame with a rubber plug, a bucket to catch the water, water and some leaves to show the movement of the water falling down. Put the plug in, pour the water in the sink with the leaves, align the bucket below the hole and pull the plug. First directly above the red painted equator line. Everybody saw the water fall super staight down. He took the sink, put it 3 meters to the right on the southern hemisphere, poured the water in the sink and pulled the plug. You could directly and easily spot (with help of leaves) the water draining clockwise. In contrast on the northern hemisphere, where the water rotated counter-clockwise.

I was standing speechless. I knew that the Coriolis effect on draining water is a common misconception, but here I saw clear clockwise and counter-clockwise rotation. What could they do to influence the water? How did they make it rotate different ways, or even straight down. The only thing I could think about was horizontal level. I put the sink frame exactly above the equator, but this time put a book underneat the right leg. The water drained clockwise on the equator, while the book under the left leg caused a counter-clockwise rotation. Just the horizontal level of the sink was what was important.

Homework:

Coriolis misconception

Wikipedia on coriolis in bathtubes

And I actually believed this..
So did you put the book under the frame while everybody was still watching? Would like to have seen the guides face. Did you get your $3 back? :).

I was asked to leave...

ze hebben geen behoefte aan ,,professoren,,

Kaart poststempel 05.08.08, ontvangen 14.08.08: uitstekend idee met reunie 2010!