>>Men working in the hat industry in the United States
Not just the US. Charlie Dodgson (who wrote as Lewis Carrol) was in the UK (and yes pedantic me had to check whether it was called 'UK' during his lifetime) :-)
BTW/FWIW he was also a photographer. I found a few online. https://www.vintag.es/2017/06/40-eerie-portrait-photographs-of.html Photography at the time involved working with noxious chemicals. He used 'wet plate' technology which required that he have his 'darkroom' along with his camera. Wet plate meant exposure time in the tens of seconds - note that his subjects seem to be mostly leaning on something and any smiles seem a bit strained.
Getting back on topic (sorry for the drift) I have to wonder if morgellons disease fits into this somehow.