Old Marker Stones

I seem to remember that these stones have been discussed before, some years ago on our old web site. They are situated at the top of The Street in Old Shoreham. One stone is marked ‘BS’ (boundary stone?) and another ‘CL’ – the other two don’t appear to have any markings. The stones must have some historical signinfcance otherwise I would have thought they would have been removed long ago – does anyone know?