I was recently sent a new book to review. It is called Cities Unfolded; London through Time. It is a zig-zag fold-out book that has one large picture of London on each page. Basically it shows the development of London from a Roman city, through to today. What a great idea for helping our children develop a sense of continuity and change over a long span of time - except by having one topic or period per page, we get no sense at all of the passage of time.