Today in Mandolin History - November 23, 1937, Guy Hart of Gibson

November 23, 1937, Guy Hart of Gibson awarded U.S. Patent #2100249 for improvements in necks for stringed instruments.

https://www.mandolincafe.com/images/thisday/2100249.jpg

This is a randomly selected event for today's date. For a list of all events that occurred on this date including internal and external links to these resources (interviews, audio files, historical links, etc.) visit the Mandolin Cafe's This Day in History.

Are there any instruments out there nowadays that use a curved trussrod like that?