Popular magazines such as Godey's Lady's Book, Peterson's, and Harper's Bazar provided women with fashion sketches, patterns, and often directions for making the garments.
But the patterns were a little different than today's. Often you would only get a simple diagram to enlarge to full size. If you were lucky there would be measurements along the edges to help you with the scale.
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Some magazines included inserts of full-size patterns, the lines overlapping crazily. The patterns came in one size, and you'd have to find and trace off just the pieces you needed, then adjust for your figure.
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Printed, full-size patterns in different sizes were introduced by Butterick in the 1860s, but they started out with just menswear. Other companies quickly followed.
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Interested in more? You can see many issues of Godey's on Google books.
Or check out this Dutch website for an archive of European fashion mags!