The 1880 census in Clark County, Missouri, indicated that two relatives were "mantamakers." The term was foreign to me.A google search indicated that, generally speaking, a mantua is type of dress. This was discovered by just googling what the word looked like and going from there. Wikipedia has a short reference on this type of women's apparel at http://en.wikipedia.org/wiki/Mantua_(clothing).
Even if you think you are reading something incorrectly, consider googling the term. If nothing else, someone else might have posted a blog entry about it!