For those in UK who haven't been watching Time Team's BigRomanDig: the prog on Saturday evening (9 July), 7 to 9 p.m., should include the excavation at Frilford, Oxon. They apparently want to focus on a circular structure carefully located by the Romans in a former river channel which is often waterlogged, and what the purpose of this strange effort might be - 'ritual' is of course the favourite verdict on anything unconventional, but bearing in mind the watery context, seems plausible here. Those outside the UK can get some info from the Time Team website via www.channel4.com/history (as if you didn't already know). Christine Buckley