Thanks, Laurie - interesting to article. The sentence "You couldn't miss him in the crowds" reminds me of that one reason for the Queen wearing outfits of such eye-catching colors and styles is security - it's easier to keep an eye on her. Lincoln however had little or interest in his protection.
The top hat (not as tall as Lincoln's though) is still part of the uniform of chimney sweeps in Germany:
http://www.prospectmagazine.co.uk/featur...ney-sweeps
Please notice the passage: "...a battered top hat in which he keeps his business cards and a notepad—his mobile office, as he calls it."