I'd never heard a bomb before yesterday and what I remember most is not the boom but the whooshing sound afterwards. Friends from Northern Ireland tell me that the vacuum left by the explosion causes this. Then came a noise of showering glass and seats and people landing on the road. I was sitting at my desk looking forward to a day of editing and meetings and my initial thought was, “I'm going to have to cancel my 10 o'clock meeting.”

Everyone in BMJ Knowledge and in the BMJ walked down the stairs and out of the back of the building. Some people were crying but nobody panicked. When I got into the courtyard, I thought I'd better go out the front and see if I could help.

There …