There you are. Ready to start a neat new project from a period source. You’re all set to sew.
And then: someone tossed carpentry into the mix?
What does it mean when you see a number on a mid-century diagram, with a little letter N after it? Or read directions indicating “nails” as a unit of measure? What the heck, Original Cast?!?
Calm your steam engines… a “nail” is simply an antique unit of measure, equivalent to 1/16th of a yard. Here’s how it goes:
36″ = 1 yard
18″ = 1/2 yard
9″ = 1/4 yard
4.5″ = 1/8 yard
2.25″ = 1/16 yard, OR 1 nail.
(Oh, and there’s also the fabric measurement of an “ell”. For our purposes, that’s often an English ell, or 45″… or 20 nails!)
Rather than do a bunch of increasingly-tiny division when your project calls for measurements like 1.5 nails (which is 3 and 3/8″, by the way), you can make a nail measure with a bit of card or firmly-woven tape, a piece of paper cut 2.25″, and a fine permanent marking pen. Fold the paper in half, and in halves again, and transfer the quarter marks to the tape or permanent card; repeat to make multiple nail sections.
(Don’t, though, hit a “normal” or “mundane” fabric shop and ask the cutter for “2.5 nails of this cotton, please.” She will stare at you, and then she will probably hate you.)