Sewing the bias binding onto the ruff was surprisingly fiddly, thanks to the variation in density between the cotton bias and the cotton lawn. Even with an embroidery sharp, it took time and concentration. I pressed the bias in half lengthwise and slipstitched it to each side individually. The ruff is only 1/4" bigger than the cuff (oops!) and not as gathered as I had thought it would be.
As I was finishing the ruffs, I was contemplating the use of hook and eyes and did a little googling. In particular at photographs of the ladies' smock in the V&A collection, which clearly shows a thread tie looped through two eyelets. I don't know if I'm brave enough to risk a handsewn eyelet yet, but I will forgo the hook & eye finish for a thread one. Oh so slowly getting there.