Historical clue formulations

• Hat decoration in a marching band — 2026-08-27
• Fancy feather — 2026-01-12
• Distinctive peacock feature — 2022-09-09
• Showy feather — 2020-04-12
• Active volcano feature — 2017-04-20
• Grand feather — 2014-11-17
• Feather in one's cap — 2014-06-18
• Smoke column — 2012-03-27
• Feather in one's cap — 2010-04-12
• Large feather — 2008-12-22
• Feather in one's cap — 2006-08-20
• Large feather — 2005-08-22
• Hat decoration — 2005-02-11
• Feather in one's cap — 2004-03-03
• Feather — 2000-07-10
• Showy feather — 2000-02-14
• Cap attachment — 1999-05-15
• Knight sight? — 1998-09-26
• Old-fashioned pen — 1998-08-25