When the closed herringbone stitch is worked on the reverse side of a semi-transparent material, it produces a double line of back stitches on the obverse side of the cloth, and creates a shadow of the crossed lines of the stitch. This form is sometimes known as a double back stitch.
Sometimes also referred to as the close herringbone stitch.
The difference between the closed herringbone stitch and the double back stitch is not technical, but visual, depending on the side of the cloth that is visible.
Source: THOMAS, Mary (1934). Mary Thomas's Dictionary of Embroidery Stitches, London: Hodder and Stoughton, p. 118.
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