Prop-Forge

I actually just got a copy of that book today and found that section. Given that it seems like Theophilus was writing around the early 1100s, and this iron piece was 1500-1600, it stands to reason there'd be advances in metallurgy to allow for a swage block hard enough to reliably make "beaded iron." Strangely enough, that was how I was thinking I'd go about it, but starting by chiseling/cutting partly into square bar before swaging, just to help start the spheres. I will say in the few photos I have, the spheres aren't perfectly uniform, but I can't imagine hammering each one of those if you have the ability to make even a crude swageblock.

Yep, that's the one. The more I look at it more closely, the more impressed I am with the original maker's problem-solving. I wish it wasn't set up so high on the wall, so one could get a better look at it. That's what I was thinking, basically divide it into cubes and treat it like you would going from square to round, with an added dimension. I'd be puckered the entire time to not break it into pieces, though.

This is from a flagstaff holder at the Philadelphia Art Museum, made in Italy 1500-1600CE. I'm racking my brain how they would have reliably made this pearl-chain sort of thing. As best I can tell, the pearls are connected as a monolithic ring, but maybe they could be rivets with a spherical head?