Editor's Note: The following photographs have been post-processed in Photoshop to optimize and restore image quality, typically including one or more of the following: correct perspective, retouch to eliminate a wide variety of non-image artifacts, and crop judiciously. Overhead wires and other obstructing objects not related to the subject of the photograph may be removed with retouching. To view the original photographic image files, use the Library of Congress link provided below.