Complex sentence: She qualified as an Apothecaries' Assistant (or dispenser) in 1917 and, as a dispenser, she earned £16 a year until the end of her service in September 1918.
Split into simpler sentences: She qualified as an Apothecaries' Assistant (or dispenser) in 1917. As a dispenser, she finally earned £16 a year until the end of her service in September 1918.