Murder on the Ballarat Train

Phryne and Dot are travelling by train to Ballarat, so Phryne can collect her new Hispano-Suiza car. However, during the journey, they awaken an unconscious woman, Eunice Henderson, who was drugged with a chloroform-soaked cloth. Also, her mother, Mrs. Henderson, seems to have vanished. They soon discover Mrs. Henderson hanging from a water tower where the Ballarat Train had earlier stopped. It is found Henderson had an argument with another passenger, Andy Cotton, who blamed her for the death of his wife, who died during childbirth when Mrs. Henderson was a hospital matron. Later, a young girl named Jane is found in possession of Mrs. Henderson's jewels. Returning home to her new residence in St Kilda, Phryne analyzes the clues to try and discover who the murderer is.