The Master Mind of Mars by Edgar Rice Burroughs

HELIUM, June 8th, 1925
MY DEAR MR. BURROUGHS:
It was in the Fall of nineteen seventeen at an officers’ training camp that I first became acquainted with John Carter, War Lord of Barsoom, through the pages of your novel “A Princess of Mars.” The story made a profound impression upon me and while my better judgment assured me that it was but a highly imaginative piece of fiction, a suggestion of the verity of it pervaded my inner consciousness to such an extent that I found myself dreaming of Mars and John Carter, of Dejah Thoris, of Tars Tarkas and of Woola as if they had been entities of my own experience rather than the figments of your imagination.
It is true that in those days of strenuous preparation there was little time for dreaming, yet there were brief moments before sleep claimed me at night and these were my dreams. Such dreams! Always of Mars, and during my waking hours at night my eyes always sought out the Red Planet when he was above the horizon and clung there seeking a solution of the seemingly unfathomable riddle he has presented to the Earthman for ages.