I wanted the reader to experience the look and feel of the department through the treasure trove of photographs available. During my many years of research for this book, I have collected photographs at every turn knowing that I would someday write Guardians of Angels. All photographs used in the book are from this endeavor and carry no caption. For photographs outside the collection, I have listed the appropriate person or institution when known. Every reasonable effort has been made to identify owners of copyrights. Any errors or omissions will be corrected in subsequent editions.