>>4788577 (PB)
And you might as well stand in the room when it happens because what happened next would be worse.
>>4788878 (PB)
KEK!!! Former RRconductor fag here. "When approaching a crossing at grade and unless otherwise prohibited, the engineer shall cause the air horn to sound two longs, a short and another long whistle, repeated or prolonged as necessary until the leading locomotive shall have entered the crossing."
Or words to that effect. That is roughly what I recall from the "Brake and Train Air Signal Instructions" book. All train crew have a copy of that catchy little title somewhere nearby. It's mandatory. The pause you are hearing is the natural result of the repetition. Dum Dum de Dum (think funeral march – although it is also part of a classical wedding march) pause, repeat.