I have a friend who's an amateur mathematician. He's run across the story of Mary Somerville, (died 1892) who was one of the first female mathematicians. According to the online articles, she solved a Diophantine problem (I think posed by Hypatia in the 5 century) and won a prize and some recognition. This was enough recognition that the establishment would have called her a "man of science", but she wasn't a man. So they coined the term "scientist" for her. She's the first "scientist."
He, and now I, would really like to know what this Diophantine problem was. Article after article mentions her success, but no one states to the actual problem. So that's my question: What was the problem Mary Somerville solved?