What was something interesting that you learned about the trombone?

Early versions of the trombone were extremely different from modern trombones.
What do they put into the tube to keep it from buckling when it is bent?
How much tubing is in a bass trombone?
How long did it take to make the custom trombone from the video?
Draw a Trombone!
What was the name of the early Belgian trombone?
What does the trem "Sackbut" roughly translate to?
Which composer started using trombones in his 5th Symphony
What is added to many modern trombones to help increase range?