You'd have to dig up stuff from the early 1800s for me to not either recognize it or not be sort of familiar enough with similar stuff to figure it out. When I was a kid, my step-grandfather used to collect and barter old junk items... Not quite antiques, because they were useless to anyone who didn't need a cog from a steam powered drill press or old side car brackets... He would come across the weirdest finds and knew who to take them to who would want them... You'd be surprised at the stuff you could still find laying on the curb in 70s NYC. One of the things I regret not hanging onto are some of the small ornate gas lamp parts and fittings and the ornate steam fittings and handles. There wasn't big money to be made at that sort of stuff... Beer money at best, but he had a fun time BSing and bargaining with his junkie buddies (what he called them, they weren't addicts). I used to enjoy looking at all the stuff in the various shops he'd go to... That was probably where I picked up a lot of knowledge about obscure mechanisms... When I got older, NYC still had a few shop like those in the China town area around Canal street... Surplus shops, used machinery, scavenged parts... It was a mad scientist and frustrated inventor's paradise. By the late 90s, early 00s all of them were gone... Replaced by generic mall shops and phone stores. Bleh... The saddest was the closing of Pearl Paint... Not a junk shop, but an iconic art supply store.