them for their kindness in giving me permission to do this. William Gilmore and Ray Williams, both of Section Twelve, supplied three and four, respectively, the latter number including the balloon pictures. Monsieur Bardellini took six of the pictures at Esnes and Colonel Thurneyssen the group of Boche prisoners. The Farnam, the bursting bomb, and Guynemer pictures I obtained from George Trowbridge.
I also have to thank Professor Harry Covington, of Princeton University, who very unselfishly devoted many hours of his valuable time in smoothing out rough places in the original manuscript. My sincere gratitude is likewise due to several friends who have very kindly helped me with suggestions, proof reading and numerous other details.
February 14th, 1918.
65 Blair Hall,
Princeton, New Jersey.
