With the Skirt
I went ahead and made up the skirt too, though I did not use the pieces from the La Mode Illustree pattern. I just eyeballed it from the fashion plate and made up my own, with some help from the skirt instructions on the pattern (Thanks soooo much to Sue Fischer for translating the French).
The skirt is a basic gored underskirt with a strip of silk pleated to the front. I then folded the vertical edges where the silk lay and stitched, almost giving the illusion that the center front silk was a separate panel entirely. It's really fussy if you can't get the silk to pleat in right. Fashion plates always show these perfect vertical knife pleats on dresses, but 9 times out of 10 you can't get them to lie flat in reality, lol.