I think it’s 14 so you can have host, hostess, and up to 12 guests. Or a pairs of spares for when a replacement is needed.

I like the notion of the napkins being cut from something else. Also, it may be that the napkins were cut from a narrow bolt. Right now I’m embroidering a 16” wide bit of lemony yellow cotton into tea napkins on a scroll frame. 8” squares, to be hemmed on three sides. I used the selvage as a skip to fourth hem and use it as the decorative edge I’m running embroidery parallel to. The finished napkins will be folded in half with the nice edge running lengthways on the right edge. The selvage edge can also be used as a firm footing to crochet, tat, or do other fancy edging work too. That tends to work better as the bottom edge of the folded napkin.

Thanks you maifleur01 and beesneeds for your responses. I don’t believe that they are home made napkins. The fabric seems high quality. They are about 17” square so the original bolt would have been about a 36” width, allowing for hems and two side by side napkins.
I’ve tried to photograph a napkin against a dark cloth too show the detail. They have a woven pattern with a central motif, ribbon and corner bows. I don’t know if this comes through in the pics. The selvedge is at the bottom.

Something that people do not remember is that fabrics used to come in different widths not the standardized ones that they have now. It would depend on the type of fabric and the intended use. I seem to remember 32, 36, 42, 48, 72 and what had the common name of bed sheet size. I also remember hatters using a narrower width of fabric. The really nice, expensive, fabrics came on rolls that were in the fabric stores in this area placed against the wall so that the ends draped in beautiful cascades.

There were napkin "blanks"....a piece of damask linen with the pattern in napkin sized squares, with un patterened spaces between....and you cut and hemmed napkins from that. Picture a long strip of cloth with napkin patterns lined up along the top and bottom. You cut each napkin out and hemmed the 3 sides. Careful seamstresses also hemmed the selvedge, but not all did.
I used to have a strip of uncut linen napkins, but don't think I still do.
14... because that's half of 28? or 2 more than 12? Or that's the number of napkins on that strip of cloth.
Back in the day.....but before the 1940's...table sets often came in sets of 18...or half that, 9. I have an old set of china....9 place settings....and have seen silver services for 9. Today we tend to think in terms of 8 or a dozen....

And back in the day most fabric widths were much narrower, especially linen. I worked in a fabric store back in the 1980s and fine linen and silk for apparel was in those narrow widths.

BUT....look again. those napkins were not made from a "width of fabric"....the design is woven into the fabric, intended to be made into individual napkins. And...these napkins were from much longer ago than the 80's.

The cloth might've been only the width of 2 napkins...

Most likely it was...that's why there is one selvedge on each....but I have old linen napkins that are much larger than that, several sets are 24 inch napkins, meaning the cloth was about 50 inches wide...if they were 2 to a width....or much narrower.
The looms for weaving cloth commercially were pretty standard widths. In my memory, cloth came in 36, 45, 52 and 80 inch widths. I remember buying 1/4 yard of fine wool, hemming and fringing to make a scarf.

There was also a 24 inch wide. Perhaps it will pop into my mind as to what it was for later. Not what it was intended for but because it was easy and I was short my mother purchased it for skirts. She used one end as the waist band and simply gathered the rest. Sometimes she hemmed but most of the time she did not.