Hello Evereyone The book Mechanical Eye by Allen Davies and Peter Stanbury is not expensive at all. As I purchased my copy 2-3 yrs ago and cost $60. However because of a tear on the cover it cost me only $30. Well worth it. If I can help anyone with dates please conatct me. REgards Grahame PS. This book was first printed in 1985 not sure if still availiable.