McMouse, many years ago, the bodies of suicide victims in the thames would be pushed from Met to City or vice versa for very same reason. Allegedly :)
My dad knew of a man, many years ago, who was walking through a park one day when he felt something go pop in his head. He immediately sat down on a bench and held his head in his hands. He stayed like that until a passerby asked if he was OK. He said no, please help me. They called an ambulance and he was taken to hospital where it was found that he had burst a blood vessel or something (whatever it was he had managed to save himself by keepig calm and very still).
If no-one had stopped he would probably have died too