In the early days of railways, the signal of alarm was given by the
blowing of a horn. In the year, 1833, an accident occurred on the
Leicester and Swannington railway near Thornton, at a level crossing,
through an engine running against a horse and cart. Mr. Bagster, the
manager, after narrating the circumstance to George Stephenson, asked “Is
it not possible to have a whistle fitted on the engine, which the steam
can blow?” “A very good thought,” replied Stephenson. “You go to Mr.
So-and-So, a musical instrument maker, and get a model made, and we will
have a steam whistle, and put it on the next engine that comes on the
line.” When the model was made it was sent to the Newcastle factory and
future engines had the whistle fitted on them.