It is the school holidays. We're standing in a queue. Children fidget. Watches are checked. It is like a visit to the Post Office. People tut under their breath. Eyes flash suspiciously at would-be queue-jumpers. Someone close by – possibly the dandruff-flecked bloke standing just in front, or perhaps the 5-year-old inquisitor inside my own head – utters the immortal words 'are we nearly there yet?'
As is predictably the case, we are not. We wait. We shuffle. We wait some more. And then at last, bingo, the clock strikes ten. Oh goody, I think as 'Cashier Number 4!' cavorts loudly through my thoughts. I wonder if perhaps the sunshine is going to my head, or maybe I really am now losing my marbles… but I have no time to ponder further as B grasps my hand and drags me forth. The doors to the Science Museum are ceremonially opened. We make our way gratefully in.