This edging is modified from a pattern in 1889 Weldon’s Practical Needlework, Volume 2. It varies from 20 to 25 stitches and has 12 pattern rows. Weldon’s version was “Dolphin Lace”. The image was cute but the pattern didn’t make the pictured dolphins and had a few errors. I renamed the edging to correspond to what it actually looks like! This edging is best attached to a straight edge.
Skills needed: cast on, knit, purl, double yarn over, slip a stitch over 2 stitches, k2tog, p2tog, e-wrap cast-on in the middle of a row and bind off in knit stitch.

Gauge is not important in this pattern. Any block-able thread/yarn and any size needles will work. Make a swatch to check size and looks.

12 yards of #10 crochet cotton will make about 33 rows (3.7”) of edging blocked in the stated gauge.