Ernest Bevin, London 

If I well remember my Churchillian readings, Ernest Bevin was a british minister during World War II. Wasn't he ? So, why "Mayor of London" ? (I'm only curious.)

Ernest Bevin was a trade unionist and labour politician, an effective member of the British Government during and after World War II and the ferry is named after him. The "Mayor of London" is a relatively recent political creation (not to be confused with the ancient office of "Lord Mayor of London" confined to the City of London) who takes responsibility for transport policy in the vast expanse called Greater London. The Woolwich ferry is free to users and costs the taxpayer via the Mayor of London a pretty penny every year - if stopped the Mayor would be obliged to create a bridge or tunnel crossing in its place. The Mayor of London signs on the ferry are merely self promotion by the Mayor of London.

Thank you very much, Nittygritty : it's very interesting. I didn't know about the Mayor of London. Here, between Quebec City and Lévis are two ferries owned and operated by the Quebec Province Government for the same reasons (a new bridge 1 km long would be very expensive).