The 21st century is ill equipped to understand what the 19th saw in hats. And the 19th century was really pretty excessive, on the heads of men and women alike. Here are some examples:

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Hats seem even more preposterous in multitudes:
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And this one may be the minimal hat:
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another:
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An anatomically explicit example:
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Perhaps this one is a bonnet:
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...and cross-hatting is fun too:
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