Why is Chicago called "The Windy City"?

In the late 1800s, Chicago evolved as a railroad center and all travel east and west came through Chicago. And it was the largest city near the center of the continental U.S. As a result it became a mecca for conventions because of its relative central location. The biggest and most covered conventions were the political parties. There were so many political conventions with long-winded speeches that a Chicago newspaper man said that Chicago had become the "windy city." It had nothing to do with the weather or Mrs. O'Leary's cown.