sentences:  Senn published 25 books as well as numerous papers and essays during his career, including the 1886 paper "Surgery of the pancreas as based upon experiments and clinical research", and the books "Four Months Among the Surgeons of Europe" and the "Nurse's Guide for the Operating Room".Throughout his career, Senn amassed a collection of 10,000 volumes and 14,000 pamphlets and articles dating from the 1500s onwards on medicine and surgery, which has been stored in the John Crerar Library.He also purchased the 7,000 volume collection of old and rare medical books left by a prominent doctor in Germany and donated the materials to the Newberry Library.