I've always been deeply interested in construction and construction techniques. The progression of construction is what interests me most with respect to costume (apparel) history. The styles unique to each era bring with them specific construction techniques that we do not often see in today's apparel unless you purchase high-end goods. While there has been a progression of techniques, it is also amazing to see that some have remained the same over centuries. This book brings a new dimension in an age when 3D and body scanning are making headway in the apparel industry. I have been somewhat involved in the repair of antique garments, but I have also altered gowns to fit the daughters of the women who wore them. I must say that past construction techniques made alteration much easier than garments that are made today. The seam allowances in particular were wider in the past making it possible to enlarge a garment that you probably could not do today without adding to the original.

While I personally have never used a foot like this, I believe that one uses it for ruffling wherein you are attaching a ruffle layer to a straight or flat layer. The reason for having a wide needle slot is to perhaps position the needle off center for attaching a ruffle to a flat layer of fabric.

If you will note, there is a screw at the rear of the foot for adjusting the depth of the pleat or ruffle.

Another thought about this foot is that it could be used for sewing two flat layers together while incorporating a flat piece of elastic which you zigzag over. This would be especially nice when attaching a flounce type ruffle to the cuff area of a sleeve as both sleeve and flounce then could be ruffled at the same time via the addition of the elastic.

Years and years ago, I remember my mother sewing a window treatment for a small window at my grandmother's house. It actually was a ruffle that had elastic down the middle of it that went all the way around the three sides of the window. It looked darling. Four rings were sewn the proper distance around the length of the long ruffle and then attached at the corners of the window via eye hooks. It really was a slick idea in that it decorated the window but did not block any light from coming in. A foot like this one surely would have been just the ticket to accomplish that task. As I recall, mother satin stitched the edge of the fabric prior to the ruffling/elastic process.

Thanks for inviting my thoughts.