3.5x5.5" full color postcard featuring the art of noted Tarzan illustrator J. Allen St. John. Originally serialized in "All-Story Cavalier" magazine in 1914, the novel was first published in book form by A.C. McClurg & Co. in 1916. Tarzan fans would write the publisher requesting information about future novels and these cards were sent out to promote upcoming books. This postcard in particular is from 1915-1916 and features brief synopsis of novel on reverse. Card bears "Powers Mercantile Co." return address but is not postmarked. Card has moderate aging/dust soiling w/some scattered small spots of darker aging/staining. Front has some surface paper wear along upper right margin. VG. Scarce. Considered among some of the earliest pieces of Edgar Rice Burroughs' collectible ephemera.