Hourglass-shaped hand drum with membranes stretched across the top and bottom of the hourglass and two strings with a bead at the end in the center.
Holding the drum by its narrow midsection and twisting the hand back and forth causes the beads to hit the drumheads.
The speed of hand movement determines the rhythm's tempo (tala).
This drum is nearly always connected with the Hindu deity Shiva in Hindu mythology.
The drum represents the rhythm by which Shiva creates the universe in his form as Nataraja, the Lord of the Dance.
The damaru dangling from Shiva's trident is another popular image.
Ascetics often carry this drum in current times, either because of its link with Shiva, its portability, or both.
Also see the classic picture.
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