Chhau masks were introduced so that you could forget your real identity and get into the role you were portraying. At first these masks were made of leaves, then wood came in, followed by pumpkin skin, then basket and thatmora and bamboo, etc.

The 108 karanas of the Natya Shastra are called upalayas in Chhau. 

Veena maestro S. Balachander took great care in storing his veena. When he traveled by train, he booked a ticket for Ms.Veena so his instrument had a berth!
(‘More than an instrument’ by Chitravina Ravikiran, The Times of India, July 14, 2014)

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