MOVE ACROSS, OR PERPENDICULAR TO, THE DIRECTION THAT THE WAVE IS TRAVELING.
Liquid is the form of matter that does not have definite shape and is not easy to compress.
Because alcohol expands over small temp changes, hence while a vial of it is used in sprinklers as the stop plug; the room gets hotter, the plug shatters.
Syrup, molasses, and honey have a lower viscosity than water