Since Anne is 19th century scientist, she would use conservative or classical methods of detecting blood traces on a glass at a crime scene because disovery of DNA was still not done. In 1853, Dr. Teichmann developed a test (also known as Teichmann test) that aim to crystallize haemoglobin when it is heated with glacial acetic acid. Since blood as haem group (hemin) and any surface that has traces of blood would react with glacial acetic acid and form crystals which can be then detected. This was one of the breakthrough discovery of that time.
