The Thorn Stitch is a line of interlaced loops resembling Single Coral Stitch, and made in the same way, except that the loops are closer together, not so large, and the needle is put in on a parallel line to where it came out.
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To work: Bring the needle to the front of the material, hold the thread under the left-hand thumb, make a loop with it, put the needle down on the right side of where it came up, and exactly on the line, and bring it out lower down over the loop of thread, and quite in its center.
Repeat the stitch, putting the needle in on the left-hand instead of the right, and continue working these two stitches to the end.