Science beats hoaxes EarthCache
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This earthcache is trying to show how, sometimes, our senses may
confuse us, how the otherwise splendid "common sense" may take us
on the wrong path.
Science over common sense (well, sometimes)
The Earth sciences teach us to find more facts about our planet and
to discover the tools and ways how to look for and at them. The
amazing inventions and excellent ideas brought to us instruments
scientifically measuring and evaluating Earth processes, shapes and
interactions. The instruments - if used properly - are much better
than our own senses. This earthcache is trying to show how,
sometimes, our senses may confuse us, how the otherwise splendid
"common sense" may take us on the wrong path.
Magnetic hills as optical illusions
All over the world, there are many places where the Earth (usually
a road) shape creates an optical illusion which is usually called
"magnetic hill" (also "gravity hill" or "electric brae" or even
"mystery hill"). Such "hill" is a place "...where the layout of
the surrounding land produces the optical illusion that a very
slight downhill slope appears to be an uphill slope..."
(http://en.wikipedia.org/wiki/Gravity_hill). There are
plenty Internet sites showing examples, photos and explanations
(sometimes scientific explanations, sometimes less scientific
"explanations"). One of the lists of magnetic hills is maintained
at http://en.wikipedia.org/wiki/List_of_magnetic_hills
(however, some of the "hills" listed there are not the Earth hills
but touristic attractions artificially created for commercial
exploration). The optical illusion is usually created by a stretch
of road in a hilly area where the level horizon is obscured.
Objects such as trees and walls which normally provide visual clues
to the true vertical, may be leaning slightly (http://www.eureka4you.com/magnetichillworldwide/index.htm)
What to look for
This earthcache brings you to such place in Philippines, not far
from Manila, but still not that easy reachable (you may need to
take several jeepneys unless you drive your own car). The place has
also its own web site
(http://www.eureka4you.com/magnetichillworldwide/LosBanos-LA.htm) -
which does not tell much but may be inspiring for one of your tasks
(described below). It is located on a side-road on the slopes of
the Mt Makiling National Park - but it is still a road so take
precautions when exploring the place. This is the place: 
How to claim the cache
- Make your own photo of the road, preferably with you or your
GPS. Or a photo that is properly geotagged.
- Try to use your GPS at both ends of the "magnetic hill". Is the
difference in elevation large enough to be observable by the usual
outdoor GPS? If yes, what difference have you measured?
- What are the instruments or methods for measuring the slope
grade (this activity is a part of a more general term
"surveying").
- [Optionally] Try a method, right on the spot, to prove
that the "magnetic hill" is rather an illusion. Photos
welcome.
Please email me the answers for 2 and 3, and log images for 1 and
4.
Once you are there...
...I recommend to visit also the "Scout camp" 
and to drive to the "National
Arts Center" (nice views, usually open only on weekdays until
16:00). 
You are also very close to
the IRRI (International
Rice Research Institute) where is located a very nice and rich
"Rice museum" (open to public in working hours). In the vicinity
(but a bit of hiking is needed), there is also another cache worth
to visit - "Sulphur from mother earth" (GC19DJ4) (visited so far
only once by me two year ago).
Additional Hints
(No hints available.)