The first policemen, known as 'Peelers' or 'Bobbies', were set up in London in 1829 by Robert Peel, the then Home Secretary, after 'The Metropolitan Police Act' on 19 June 1829.
Can you spot the difference?
Left: City of London Policeman. Right: Two Metropolitan Policemen
Making use of the newly-invented telephone, Police Public Call Posts allowed officers on patrol to keep in touch with the local police station in the days before personal radios. A light on the top would flash to attact the attention of a passing policeman. The public were invited to use the telephones, both in emergencies and for more routine queries.
A Police Signal Post Box - 1880s
They contained a telephone and a separate locable cupboard for first aid equipment
The police "signal post" appeared on the streets of London in the 1880s. They were followed later by the classic "Dr Who" police box launched in the 1930s.
A 1930s "Tardis" police box in Earls Court, London
in Trafalgar Square, London
The two identical police boxes in Trafalgar Square in London are each hidden inside a stone pillar topped by a lamp from Nelson's ship.
The traditional 'blue lamp' outside a police station in London
It's Fathers Day :)