Dear consuelo: the wires do indeed assume the catenary curve. That is so much taken for
granted that I had never heard the word in that connection. These days trains with overhead
trolleys and wires are uncommon. I think I remember a time when some cities made railroads
through the city be elctric, but haven't ridden a train in a long time. I did find one URL confriming
your statement:"The overhead wires, known as catenary wires, deliver power to the electric train
as it travels along the track. Given the distances involved, this is a more significant undertaking in
an intercity application than within a city."