Corrugated ribbing

Corrugated ribbing is a classical element of Fair Isle knitting. In corrugated ribbing, the knits and purls are worked in two different colors using stranded knitting. I’ve searched through my books on Shetland knitting to try to find out when corrugated ribbing became such a central element. But none of my books comment on that specifically. In Alice Starmore’s “Book of Fair Isle Knitting” there is a photo of the earliest known Fair Isle hats, from around 1850. They are covered in OXO pattern bands, but none of them have corrugated ribbing. On the knitting famous portrait of the Prince