Awesome Wine Glass Music: Glass Xylophone!Glass Xylophone is a percussion instrument similar which use Water Glasses with different amount of water for different tones.The more water added to the glass,the pitch or frequency gets lower.Because when you add water, you also add more mass to the bottle —the combined mass of the bottle plus the water. More mass results in a slower/lower vibrating frequency, and less mass produces a faster/higher vibrating frequency. To play the instrument, lightly tap the side of the glass with the spoon.