The first arrest by telegraph took place in 1845. John Tawell poisoned his mistress at her home at Salt Hill and fled by train to London, but police sent the following memorable message ahead to Paddington Station:

A MURDER HAD JUST BEEN COMMITTED AT SALT HILL AND THE SUSPECTED MURDERER WAS SEEN TO TAKE A FIRST CLASS TICKET TO LONDON BY THE TRAIN THAT LEFT SLOUGH AT 7.42 PM. HE IS IN THE GARB OF A KWAKER [the instrument lacked a Q] WITH A BROWN GREAT COAT ON WHICH REACHES HIS FEET. HE IS IN THE LAST COMPARTMENT OF THE SECOND FIRST-CLASS CARRIAGE.

In a London coffee tavern Tawell was confronted by a detective who asked, no doubt triumphantly, “Haven’t you just come from Slough?” He was jailed, tried, convicted, and hanged.