"that is used for fixing the handlebar/fork when you lean the bike to a wall - so it wont fall down. in theses days bicycles usually didnt have a kickstand, they were always leant to the wall. i will show you when we meet :)"

"same here - 1915."

"that means 1915 - so the hub is from 1915. but that does not mean the bike is from 1915, you must know that a lot of older parts very used for bikes after WW1 - cheers max"

"Or is it 339509? Remove paint there with steel wool"

"Nagyon jó!"