Whistle post
From Wikipedia, the free encyclopedia
Image:Whistlepost.jpg A whistle post, in railroad usage, is a sign marking the location where a train engineer is required to sound the horn or whistle.
Whistle posts in the United States were traditionally placed about 1,500 feet in advance of a road crossing.
The signs in themselves varied in design from railroad to railroad. Some were marked with - - o - (two longs, one short, and another long) in the manner of Morse Code. This sequence is known as Rule 14L in almost all railroad operating rules.
Modern whistle posts are of simple sheet metal construction, utilizing a 'W' marker. Multiple crossings protected by a single sign have an 'X' displayed below the 'W'.
