Antique French Knife Rests, set of 6

You probably saw these fabulous knife rests on my main blog some time ago. I had never seen knife rests like these, with the little cups on either side. I think they could be for individual salt and pepper helpings for the diners, so that they don't have to pass one large salt/pepper cellar round. The French usually have those double salts on the table rather than salt and pepper grinders/shakers -