Cables? Why not saddlebags?

In reading the ongoing WikiLeaks press coverage, my magnety detector from this earlier post sounded again. Isn't it curious that a set of contemporary electronic messages are described as "cables", which seem like lost artifacts that a Western Union delivery person might once have carried? Why not saddlebags, like the message containers the Pony Express would have used, or perhaps ancient receptacles for cuneiform tablets, assuming there's a name for such items? Excuse me; I must now also dial my telephone, though I haven't moved a finger in a circular fashion to do so for some time.