Sound in water and solids
Sound does not travel only through air. It travels faster through water, and faster still through solids.
In water
About 1400 metres per second. Messages can be sent through water, and whales communicate with one another using sound.
In steel
About 5000 metres per second. That is why the sound of a distant train can be heard clearly through the rails.
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A snake hears through the ground
A cobra senses vibrations in the ground through its lower jaw bone. The vibrations are carried through the bone to its ear, so it can hear the footsteps of animals it could catch.
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