Karen.... John's ruler?

[Randi]

I have this metal ruler that was John's. it has the name Bacher on it. On both sides it has different measures, but I have no clue what they are, except for centimeters. On one side, it has 2 P, 48 P and centimeters, and on the the other side it has 8 P, 9 P and 10 P. Do you know what the P means? I can't figure it out. I know that 1 inch is approx 2,5 cm.

[Husky_mom]

if you post a pic might help.. it could be a scaling ruler

[Karen]

P is for pica - a term used in publishing, and sometimes point - as in point size.

There are 12 points in a pica, and 6 picas in an inch.

[Lady's Human]

Printer's ruler? In which case the odd measurements are Picas.

And I've been forum ninja'd by my sister.

[Randi]

I thought you'd know Karen, thank you! I have heard picas mentioned, but never really thought about it - it's still confusing, though. It seems that 60 on the 2P line is equivalent to 15 on the 48P line - and 40 on the 10P line is the same as 50 on the 8P line. Hmm! I'll figure it out tomorrow, when I'm not sleepy.

Btw, John used to be a draftsman (mechanical engineer) before getting into photography and later illustrations. So it must be from that period.

[RICHARD]

It's used to measure the feet of Picas.....

For Pica shoes!

[Lady's Human]

Thank god we don't measure shoes in picas, some of us would need scientific notation.