and naturally, the one that I missed, and I can't get the beeb i-player in Ireland
In answer as well to the stone on the Jewish grave...
"Even when visiting Jewish graves of someone that the visitor never knew, the custom is to place a small stone on the grave using the left hand. This shows that someone visited the gravesite, and is also a way of participating in the mitzvah of burial. Leaving flowers is not a traditional Jewish practice. Another reason for leaving stones is to tend the grave. In Biblical times, gravestones were not used; graves were marked with mounds of stones (a kind of cairn), so by placing (or replacing) them, one perpetuated the existence of the site."
