Over the last two weeks, train industry executives and others have been talking more about natural gas, as meetings in Houston and Chicago highlighted interest in a fuel that could slash one of the railways' top costs.
Representatives from major rail companies and related manufacturers met in private at a Houston hotel conference room last month to talk about how to push forward what could be the next great shift in train technology - a cataclysmic transition similar to the move decades ago from coal to diesel power.
