You weren’t far off! Here’s a write up on the shape and it’s origins…
https://www.smokingpipes.com/smokingpipesblog/single.cfm/post/sixten-ivarssons-peewit-evolutionary-step#:~:text=In%20his%20Still%20Searching%20for,the%2050s%20—%20during%20which%20he analytics ca
