Aquinas' definition. The Oxford Concise Dictionary of the Christian Church defines acedia (or accidie) as a state of restlessness and inability either to work or to pray. Some see it as the precursor to slothâone of the seven deadly sins.
A train horn is a powerful air horn that serves as an audible warning device on electric and Diesel locomotives. The horn's primary purpose is to alert persons and animals to an oncoming train, especially when approaching a grade crossing. The horn is also used for acknowledging signals given by railroad employees, such as during switching operations.
Train horns must be sounded in a standardized pattern of 2 long, 1 short and 1 long blasts. The pattern must be repeated or prolonged until the lead locomotive or lead cab car occupies the grade crossing. The rule does not stipulate the durations of long and short blasts.