Colthrop Siding

The dog chart and associated locking table, derived from the dog chart, show the situation in 1970. The redrawn dog chart and the associated locking table, derived from the dog chart, show the proposed situation in 1971, to allow disc 12 to read to three routes. In fact disc 12 and associated connections were removed in mid 1971. The box diagram has been published in 'Signal Box Diagrams of the GW and SR by Pryer, volume 20 - GWR Berks and Hants Lines, page 20 and is available from the Signalling Record Society.