Have you ever noticed a change in the \"whistle" a train makes as it rushes by? If you stand by the tracks while the train is passing, the sound gets higher and then lower as the train goes by you. ...
A HIGHWAY OVER WATER
There is a highway in Louisiana that you can ride on for 24 miles (39 kilometers) and see nothing but water on both sides. It goes right across the middle of Lake Pontchartrain, the largest lake in...
