Pieces based on a 'procedural score' for composition with environmental sounds. The title track, made in 1967 is a very early environmental composition and is fascinating, as well as being of historical significance. All the other works are later orchestrations evolved out of different readings or electronic analyses of this one recording, three electronic and one for acoustic instruments, all of them mostly drone-centred. For me, the acoustic piece is far and away the best. In fact this 1980 work and the original 1967 recording, are reason enough to buy this CD.