I remember reading about beavers’ castor glands (not actual glands) when I was going through my trapper and mountain man phase in elementary school. (Everybody went through one of those as a pre-teen, right?) As I recall 18th and 19th Century trappers would harvest the pelts to eventually be sold to hat makers and harvest the castor glands to mask the human scent on their traps. At least that’s how I remember it from 40+ years ago.
