The combination square you describe is in Walters on page 595. (Stanley
No. 21) Sounds like yours is the same vintage as mine, only I have the
12". Walters says the came in 6", 9", and 12" sizes. 

When you say "all steel" not sure what you mean. Most of the frames are
cast iron, japanned black, but mine (and maybe yours?) is nickel plated.
Walters doesn't mention this (unless it is a typo and it means to say
"Finish: Japanned, polished or nickeled FRAME" -instead of BLADE. Has
anybody seen a nickeled blade???) Someone told me that the nickel frame
was found in only one Stanley catalog of the period (I forget what year,
but seem to recall it was in the 20's). I don't collect paper at all, so
couldn't say for sure.

The slotted ruler is an interesting design. I don't know much about other
combination squares (my user is a nice old Starrett) but the slotted
ruler does seem to give one the option to use it as a bevel gauge, in
addition to the usual 45 degree/ 90 degree orientation. 

Darren Addy
Kearney, Nebraska

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