This free pattern originally published in the Woolco Knitting & Crocheting Manual, in 1916.

MATERIAL-6 skeins Woolco Germantown Zephyr. 1 pair No. 3 Woolco needles.
Cast on 72 stitches.
Knit 2, purl 2, for 9 rows.
On the 10th row make holes for rubber.
Knit 22 rows more, knit 2, purl 2.
From now on knit plain forward and back.
Knit 8 rows.
TO SHAPE THE KNEE-Knit 43 stitches; turn, knit 14 stitches; turn, knit 15 stitches; turn, knit 16 stitches; turn, knit 17 stitches; turn.
Continue adding 1 stitch in this way until all the stitches at each end of the needle are used.
Knit 20 rows plain.
Narrow 1 stitch at each end of the needle, every 3d row, 9 times.
Knit 4 rows plain.
Knit 2, purl 2, for 27 rows.
GUSSET-(Knit all the widening stitches plain; the others, 2 plain, 2 purl.)
Knit 12 stitches; at the 13th stitch widen 1 stitch; also widen 1 stitch at the 28th stitch.
Knit 3 rows.
On the next row widen at the 14th and 29th stitches.
Knit 6 rows.
On the next row widen at the 15th and 30th stitches.
Knit 6 rows.
On the next row widen at the 16th and 31st stitches.
Knit plain forward and back for 5 rows; bind off.
Finish with black elastic.
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