Originally Posted by miriam
Some kind of hemmers looks like it would fold fabric - I don't know how they work - they were in the same box
These are both tuckers or tuck-makers - they're wonderful toys if you like fine vintage sewing. :)
While you're sewing beautiful little tiny pleats, the tucker is marking the next line of sewing with the automatic equivalent of a hera marker.
Tucks are a great way to put some fullness into a garment - at the shoulders of a blouse or nightgown or on baby clothing. You can also tuck yardage before you cut out sections of a garment and have a nicely detailed yoke on a shirt or skirt, for instance.