Read H.V.Morton's biography St Paul's Cathedral seen through the smoggy haze of a 1920s afternoon.
Men are like flat figures cut in black paper.
All things become two-dimensional. Carts, motor-cars, omnibuses are shadows that nose their way painfully like blind beasts. The fog has a flavour. Everywhere the fog grips the throat and sets the eyes watering. It puts out clammy fingers that touch the ears and give the hands a ghostly grip.