Koku 虚空 - "Empty Sky". Un Ryuu

Koku 虚空 - "Empty Sky". 

Legend has it that a founding monk of the Meianji temple in Kyoto, Kaiso Kichiku (or possibly Kyochiku), climbed Asama-yama and spent the night in the Kokuzo meditation hall atop the mountain. In a mystical dream he heard this melody. Koku, which literally translates as "empty sky," is on of the three main pieces of Japanese honkyoku music for solo shakuhachi, (along with Mukaiji and Kyorei). It is also the longest and most melodic of the three.

p.s
Everything is sacred: the trees, the sky - the land under me. Play the flute Honkyoku and bring harmony to the world - that's good. Play Honkyoku as the last breath of your world - it will be a prayer for all the prayer of all living beings. Listen to music of the wind, and then listen to the music of silence - it's gorgeous. Za-Zen practice - is to be with himself.
Sitting in practice Za-Zen - is to drink tea with the Buddha.)
Wash your cup of tea or after plate after a meal - it's clean your mind))
From Heart to Heart.
Sincerely,
Un Ryuu.