Pitch♪er
A xylophone meets a pitcher.
Listen to the pitch of the sound made when the pitcher is hit. Compare it with the pitch of the handle (working as a tuning bar) to know if the pitcher is empty or not.
That way you won’t bother to open the lid while having fun.
This work is licensed under a
Creative Commons Attribution 3.0 Unported License.
petitinvention 