That is fantastic, with steel bench too, took a fork lift to push it in there and could have broken. The roundball end on the screw says it is 1930s or earlier I do believe. Thanks for posting.
** the roundball end been abused and brazed repaired.
Yost made them like that until ~1970.
**i didn't know this, maybe not as old as i thought. for some reason i thought meadville yost were somewhat prewar. thanks.