Excellent answer Bugbear, A question ive carried for years, seemingly solved in a matter of hours
First picture you show seems to be just the one. I googled William Fairham and his book is free on Gutenberg......Result !!
"Mitreing a Moulded Door Frame.—Fig. 333 illustrates the method of mitreing the moulded portion of a door frame where the joint is dowelled, not tenoned. A small wooden template is made out of beech or other hardwood, having its ends cut at 45 degrees. This template is placed on the rail, as shown, and held in position by placing both the rail and the template in the vice. The face of the template forms a guide for a wide chisel, and enables the worker to gradually pare away the moulding to the correct angle."
Having read the description above of its use, it refers to "Made out of Beech and held in the vice"......I presume the small Cramp shown is the "Vice", I do have difficulty with the picture matching the description. Wouldn't short grain become an issue with the long
and short feet?
Embarrassingly I didn't reach for my copy of Joyce either, shame on me
.....after some rummaging I see its a "wooden Mitre Template" page 229 fig 224 ?, without the second "Foot", the same one as found in the TATHS publication also. Much the same shape as Biliphuster's metal version.
Biliphuster; Maybe the perfect semicircle cutaways are allowance for a round section G-Cramp (Inspired by Bugbears first picture above), if used with particularly thin stock ?
How would one use this item with the long "foot" on top of the wood, the 45 would be inverted, would it be used horizontally instead?
Maybe as Jacob says, its a marking tool after-all, nothing to do with paring ?
Regards,
Dave