IN the preparation of this book I have received help from many people to whom I am greatly indebted.
To Paul M. Angle for much competent advice and criticism.
To the Misses Inez Awty, Vivian Bolotin, Sally Holmes, Blanche Novotny and Sally Owens for their literary judgment which played an important part in the composition.
To Mr. David Rankin Barbee, who has contributed much to my knowledge and who has given to me some of his treasure of unused data. The chapter on Hanscom is entirely due to his cooperation, and it was he who turned my attention to William P. Wood.
To Mr. Luther H. Baker, son of the late Lieutenant Luther B. Baker, who has imparted to me interesting recollections.
To F. Lauriston Bullard for helpful and valuable criticism.
To Professor John W. Curran, of the DePaul University College of Law in Chicago, who is second to none in his knowledge of the conspiracy trial, and who has assisted me in many ways.
To Mesdames Cathryn Churchill and Meta Caminer for their patience in deciphering and retyping the manuscript.
To Messrs. H. E. Crawford and George E. Mierkle of the Metropolitan Police Department in Washington, who have given me much of their time, and whose records have enabled me to write the chapter on John F. Parker.
To the late John H. Dern, Secretary of War, who permitted the publication of material found in the files of his department.
To Mesdames Gertrude Garrigan, Kathe Thompson, Rea Hyman, Beatrice Jaros, Gertrud Brink, Pearl Hight, Ann Breitowich, Dr. Helen Lemberger and Mr. Charles Tyng for the time they gave to historical research.
To Mr. Alexander Hannah for his kindness in permitting me to use his collection.