PEBBLES TO COMPUTERS: THE THREAD. Blohm, Hans; Stafford Beer; and David Suzuki. Toronto, Oxford University Press, c1986. 112pp, cloth, $24.95, ISBN 0-19-540536-6. CIP Grades 11 and up Reviewed by Jean Farquharson Volume 15 Number 1 1987 January To read this book is an experience. Hans Blohm, the originator, travelled all over the world to photograph items from prehistory and antiquity that he could relate to today's high technologies. Stafford Beer, scientist, philosopher, painter, pioneer or cybernetics, and an international authority on the science or organization, wrote the text for this innovative book. David Suzuki wrote the introduction. The book is more than a history of computation. The threads or "connexions" link pictures and text from page to page, organizing our perceptions of past and present, nature and technology, science and philosophy, in a unique way. For example, the first picture is of wet pebbles, all different, all entities, all representing an abstract concept of a physical unit, something that can be counted or used as a ballot. The pebble computer, a disc-shaped rock, sectored and with concentric wings, bears a strong similarity to a computer disk; although far apart in space and time, both are used for basically the same purpose. Artifacts such as cave drawings, pictographs, Stonehenge, clay tablets, geared calendrical devices, astrolabes, and clocks are described and related to "all efforts of mankind to record time and memory, to create order out of chaos." The beauty of this book is the reaching out, McLuhan-like, in so many different directions to make the connections. It would not be very useful as a history factbook, but rather as an enrichment tool to inspire a bright student. It is a book to be picked up again and again, meditated upon, and savoured. There is no index, only a short bibliography, and a list of plates. Jean Farquharson, Brantford C.I. & V.S., Brantford, Ont.