vintage sewing patterns

Oh dear, I have a bit of a new obsession - vintage sewing patterns. And the internet makes it so easy (although not easy on the bank balance, they can be really pricey!)

I am loving the lines of the designs from the 1930s. I bought this one on the left but sadly missed out on the one on the right.






















I do have a number of questions though about these vintage patterns - firstly about size. How do the vintage sizes compare with current sizes? I am confident that I am a modern 14 but I know that these old patterns were drafted very differently. And the brands - my internet travels have come up with Hollywood, du Barry, and Advance as well as the familiar Simplicity, McCalls and Vogue. Any opinions?