Slug facing wheel? Help identify

There are rotary miterers, this might be one, though I can’t see if there is an adjustable work holder here. There would be a blade set into the wheel, and it would shave material off the slug with each rotation. Miterers can be set to 90 degrees (as well as other angles), and used for smoother or more accurate finishing than hand or bench slug cutters give.

Yes that’s it! Thank you for the help! Very cool little piece.

It’s a mitering wheel.
When making a type high box the ends of lead or brass rule are mitred at 45 degrees and hopefully get a perfect join that does not show when printed. Also used at other angles such as for diagonal lines in an advert to get perfect joins at the ends. Often used to trim small amounts off the ends of leads when putting together a tight forme.

Back in the day in the City of London trade that thing was called a ‘bowler’ pronounced like the hat. I have two, and never use them, any offers?. As someone said they were vital to get accuracy, of box rules round things. A glance at the small ad columns of any letterpress period newspaper will show the standard of craftsmanship in that shop! When used on Monotype product strip borders one had to be very careful indeed to make the border units fit round the corner,
useful as a test for the apps. ( Thats apprentices not some computer programme).