We're leaving the house of roses, dogs and trains where we have been well loved and cared for.

During our stay, I've been listening to train horns.

There is more than one call (and many codes and sequences depending on what's being communicated, train company, country, and operator style and technique). There is the traditional sweet lonesome. There is a more raucous, dissonant call. According to a Wiki article under 'train horns', horns in the US have been made by various manufacturers, each offering different notes and equipment. Some are sounded using cords, some with levers. Those recently manufactured have push buttons that give less control to the operator. Train horns are air horns, with a 'bell' like a bugle or trumpet. Each train horn has one to five horns, a single note to a full chord. I suspect doubles are most common, though I think I've heard a single-note horn and a three-noter. Fives are rare because of the prohibitive size and weight of the equipment. When alone, I like to try to tease out and reproduce each note being sounded.

(A young woman studying music at Texas State told me about individuals from other parts of the globe who can, with much practice, sing two notes at once. She said there are some who can sing three notes at one time. Human train horn.)