http://www.rssboard.org/rss-specification 720 XTF Search Results (docsPerPage=100;f70-subject=Railroads -- Signaling -- Block system) https://catalog.wrhs.org/collections/search?docsPerPage%3D100;f70-subject%3DRailroads%20--%20Signaling%20--%20Block%20system Results for your query: docsPerPage=100;f70-subject=Railroads -- Signaling -- Block system Thu, 01 Jan 1970 12:00:00 GMT Alternating current block signals on the Southern Railway. Eck, W. J., General Railway Signal Company https://catalog.wrhs.org/collections/view?docId=marc/skclmarc202890322046876.mrc https://catalog.wrhs.org/collections/view?docId=marc/skclmarc202890322046876.mrc Thu, 01 Jan 1970 12:00:00 GMT