This paper is an extract of “Selected Writings” published in English by Heiner Friedrich in 1969. It contains some notes on Map of 49's Dream the Two Systems of Eleven Sets of Galactic Intervals Ornamental Lightyears Tracery, a collaboration between La Monte Young (sound frequencies) and Marian Zazeela (lights and models). This work is an extract of The Tortoise, His Dreams and Journeys. It is constructed through sets of frequencies applied to sounds and lights. The two artists lived in this environment for several months studying the influences of these frequencies on humans.

Cet article est un extrait de Selected Writings publié en anglais par Heiner Friedrich en 1969. Il contient un certain nombre de notes sur Map of 49's Dream the Two Systems of Eleven Sets of Galactic Intervals Ornamental Lightyears Tracery, une collaboration entre collaboration La Monte Young (fréquences sonores) et Marian Zazeela (lumières). L'œuvre est un extrait de The Tortoise, His Dreams and Journeys. Elle est construite autour d'une série de fréquences sonores et lumineuses. Les deux artistes on vécu dans cet environnement pendant plusieurs mois afin d'étudier l'influence de ces fréquences sur le corps humain.