The index that lists magazine articles according to subject is the Readers' Guide.
The Readers' Guide has been published since 1901 by The H.W. Wilson Company. It is used in public and academic reference libraries alike throughout the United States.
Partridge could see what Phoebe was doing even though she couldn't actually see her". At the end of the novel, we learn that she has been responsible for leaving those secret messages on the Winterbottom doorstep.
