Just come across your very old query about Florence Matthews and wondered if you had discovered by now that Florence's mother, Elizabeth Johnson, is the daughter of Sgt. Thomas Johnson of the 4th Dragoons and Khatun, a Persian lady whom he met and married while serving in Tehran in 1837. My g-grandmother Ondar Anna Johnson was Elizabeth's elder sister and born in Persia. I have marriage certificates to confirm all this and much more information besides if you would be interested. Khatun (spelled Kattoone) is the second name of Elizabeth K Matthews whose photograph you posted and Florence had a younger sister named Ondar.