Brass Paper Fasteners: a Folded Strip under a Domed Cap

A paper fastener is a soft brass split pin with a round head: push it through punched paper and bend its two legs apart to hold the sheets, or to make a joint that turns. George W. McGill patented it in 1866. Fold thin brass strip over a rod into two legs of slightly different length, and crimp a small domed cap over the fold. The picture: brass paper fasteners, one without its cap showing the folded strip.