Water
CylindricalGlass
TwoArrowsonaCard
Placethearrowcard
nearthewall.
Placeaglassinfrontofthecard.
Fillwaterintheglass
tocoverthelowerarrow.
Magically,thelowerarrowwillreversedirectionandappearlarger.
FunwithWaterLens
1
2
3
4
Onpouringwater
intheglass,it
actslikeaconvex
lensandinverts
thedirectionof
thearrow.
37