So what was the well-dressed young woman wearing in 1809?
If she were out for a stroll in spring or summer, she might wear this (Promenade Dress, July 1809, Ackermann's Repository):
How about evening wear? If you attended the grand reopening of Covent Garden theatre in 1809 after its rebuilding following a disastrous fire in 1808, you might wear something like this (Opera Dress, March 1809, Ackermann's Repository):
Or maybe you've received a coveted invitation to dine and hear a concert at Carleton House, London home of the Price Regent. If so, this might fit the bill (Full Dress, April 1809, Ackermann's Repository):
And of course, the all important ball...(Ball Dress, October 1809, Ackermann's Repository). This is "A light blue, or grey chemise robe, of gossamer net, imperial crape, or Spanish gauze, worn over white pealing satin, ornamented up the front with French bows and knots of silver. A full melon sleeve, formed of the same material as the dress, and alternate stripes of white satin; finished with bows and knots of silver.":