Plague doctor...the "beak" would contain herbs that would help to protect the Doctor from contracting the disease. It was basically useless...of course they didn't realize how disease was spread and the different methods of cross contamination, etc...
10 things you (probably) didn’t know about the Black Death - It is one of the worst catastrophes in recorded history – a deadly plague that ravaged communities across Europe, changing forever their social and economic fabric. But how much do you know about the Black Death? | History Extra
These bawdy pilgrimage badges found in the Netherlands, France and England, dating from roughly 1350-1500, functioned as apotropaic, or protective devices, meant to safeguard their owners from the threat of the evil eye, which during the worst outbreaks of the Bubonic Plague, was thought capable of transmitting the disease.
Plague doctors in the and century wore these creepy masks to avoid breathing in putrid air, which they believed would cause infection. The beaks were filled with perfume. Popular scents were balm mint leaves, ambergris, cloves, camphor, myrrh, and rose.
"As may be seen on picture here, In Rome the doctors do appear, When to their patients they are called, In places by the plague appalled, Their hats and cloaks, of fashion new, Are made of oilcloth, dark of hue, Their caps with glasses are designed, Their bills with antidotes all lined, That foulsome air may do no harm, Nor cause the doctor man alarm, The staff in hand must serve to show Their noble trade where'er they go."-Dr. Nathaniel Hodges