c1830 Mens Underpants or smalls. With the lengthining in mens trousers as we leave the Regency era; changing from breeches to pants so did their "unmentionables". The front view can be seen at http://www.metmuseum.org/collections/search-the-collections/80002462?rpp=20=1=on=*=Underwear=1
I think you need one of these outfits ;) Burgundy Regency Coat over your shoulders and cut a gallant figure at your next festive event. Designed in the cut-away style found in early 19th century fashion, this men’s coat is ideal with our Fall Front Trousers for a true period look.