This period of time Jane Austen wrote during was known as the Regency period. Before this period was the Elizabethan and Georgian periods. Remember Queen Elizabeth? She wore INCREDIBLY fancy outfits - big wide dress bottoms, giant fluffy tops. It was extremely complex. In comparison (and perhaps as a backlash against that) this was a much different style. People of the time joked that you could fit an entire dress in a pocket if you balled it up, it was so insubstantial. It was modeled on Greek and Roman outfits.
Regency Period and Jane Austen
The muslin was thin and clung to the body. It was as if women were walking around in nightgowns. Before 1800 the waist was a bit below the bust, but by the early 1800s the waist was immediately below the bustline and fell straight from there. It gave the illusion of extremely long legs. Because there was only candlelight at night, evening dresses were often very bright white, with metallic sparkles, so that the woman could show off her outfit. A dark or complex design would be invisible.
During the daytime, women would often wear a thin piece of fabric called a "fichu" around the neck to cover up the open busom area of the dress. This was both for modesty and to keep the wearer warm. However, in the evening they would often remove this for a more fancy look.
Here are some dresses that I love from this period. They are great for getting ideas for making your own dress!
Description of the above two white dresses shown from the Museum of Modern Art
Antique Musin Dress from 1800-1820
Historical White Dress from 1804-1811
Lizzie and Charlotte in the A&E Pride & Prejudice
Making your Own Regency Dress
This painting is "Pinkie" by Sir Lawrence, done in 1794. This would be the type of character Jane originally had in mind.
This one is Fanny and Jane Hamond by Sir Lawrence, in the same time period.
Regency Period Information