During the long march of progress (or was it June?) the invention of the wheel proved to be of great benefit to man and womankind. Just how far it's rolled since then can be seen in tonight's programme, which is devoted almost exclusively to transport. Tom and his regular team of CHRIS EMMETT. CAROLINE GRUBER. JEFF STEVENSON and MICK WALKER are joined by guest Adrian Walsh (if his bus arrives on time) in a lighthearted look at the merits of timetables and trains, boats and planes. Why is it that buses always arrive in threes? Why do train platform announcements sound like frying porters' hats? Why is an aircraft named after an elephant (if they can't fly)? Fancy calling your pet elephant Concorde!