Doctor Sahndrah Lywys was a Charisian citizen and scientist.  During the 890s of God , she was a member of the faculty of the Royal College of Charis, specializing in chemistry.

In April 896, she accidentally discovered guncotton when she used a cotton lab apron to wipe up spilled Schueler's tears and vitriol distillate (or, to use the Terran names, nitric and sulfuric acids), then held the apron near a lamp to dry.  (MTAT)

Her nomination as a member of the Inner Circle was still pending at that time, due to Father Zhon Byrkyt's final illness.  Her discovery, and the need for her to have the additional information stored in Owl's memory to put it to full use, meant Merlin and Rahzhyr Mahklyn pushed harder for her to be cleared.  By August 896, her nomination had been approved.  (LMA)