Based on a pattern from _The Priscilla filet crochet book; a collection of beautiful designs in filet crochet, equally adapted to cross-stitch, beads and canvas, with working directions_ by Robinson, Belle; Priscilla Publishing Co (1911) p42.  This version adds minuscule letters and basic symbols, and much simplified to emphasize the "holes" from the inspiration, removing side flourishes and flowers(?) that were the main elements of that design.  To see the inspiration go to https://archive.org/details/priscillafiletcr00robi/page/42/mode/1up