- Those who made corset patterns for the larger companies will have been highly skilled time served professoinals, who had little or no need for commercial patterns, but who had an innate sense of the human body, and a good working knowledge of anatomy.
Not much different from today really.
There will doubtless have been books out there that gave an idea to the women (not many) who were unable to buy ready made corsetry. If the books already suggested that have patterns taken from extant pieces are of no use, then you'll need to head to a national library, such as the British Library, Library of Congress, or Biblioteche National.
There were also several corset paterns appearing in various dressmaking and home magazines of the later 19th century, again, aimed at hoime dressmakers.
They *may* have something of what you are after.
You may also find something online.
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