In the 1970s, German photographer and filmmaker Dieter Appelt first saw the Forth Rail Bridge, built in 1890 to cross the River Forth in Scotland. The spectacular cantilevered steel span, a marvel of 19th-century engineering over 8,000 feet long and still in regular use today, fascinated him with its kinetic and cinematic appearance. Invited by the Canadian Centre for Architecture to work with its collection for the mixing-of-disciplines Tangent series, he found photographs of the bridge in the archives and then revisited it in person. In keeping with his longstanding practice of analyzing architectural constructs in spatial and temporal terms, he produced a work of 312 black-and-white 35mm film stills and sound recordings. As Appelt says, "It is an organized dance of signs." The book contains some of CCA's archive photographs as well.