It came to my attention that there's an old (1770) French book about shaving known by "La Pogonotomie" (actual title much, much longer).
Gotta love those Enlightenment French people!
The book is (obviously) out of copyright and available online for free.https://archive.org/details/lapogonotomieou00perrgoog
Apparently there's a whole chapter on coticules, which I'm interested in. Unfortunately I can't read French. So I'm just leaving this here in case anyone who can read French wants to read it, and if anyone who has read it wants to comment, summarize or leave a review.