Artist's book by Allan Kaprow documenting his happening ECHO-LOGY, which was carried out by a small group of people moving in the water of a stream in Far Hills, New Jersey on the weekend of May 3rd and 4th, 1975. It was commissiond by the Merriewold West Gallery. Book comprised of photographs of the happening in process and texts by Kaprow. Photographs by Lizbeth Marano.