Yours from the Tower by Sally Nicholls
 
Tirzah, Sophia and Polly are best friends who have left boarding school and gone back to very different lives. The year is 1896 - Polly is teaching at an orphanage, Sophia is scouting for a rich husband, and Tirzah is stuck as an unpaid companion to her grandmother.
 
In a series of letters buzzing with atmosphere and drama, the friends air their dreams, hopes, frustrations, and romances. Can this trio of very different young women find happiness and love near the dawn of the Edwardian era?