... you might already know- is that the bolt comes up through the sleeper and then the chair with the nut being screwed down from the top. This made it a whole lot easier for them to experiment with concrete sleepers. The info that I vaguely recall on their early (? earliest) efforts was in the 1930s- probably in either the Engineer or Engineering. posted: 3 Mar 2015 21:18 from: Martin Wynne Concrete sleepers and GWR 2-bolt chairs. I took this photo on 13th July 1968. 2_031551_430000000.jpg An occupation bridge near Hartlebury on the Severn Valley branch. Apart from the tidy track, what is striking in this picture is the quality of workmanship in the bridge with neat dressed masonry and graceful curving wing walls. For a simple occupation bridge. There were thousands of similar bridges all over the country -- but if a single one was built like this today it would almost certainly qualify for an architectural award, media coverage, and an opening ceremony. Passenger services on this line had ceased within 2 years, and ...