"The Encantadas, or Enchanted Isles" in Putnam, purporting to be written by Salvator R. Tarnmoor is unquestionably from the pen of Herman Melville, author of "Omoo," "Typee," &c. The story is in his best vein.The Encantadas, Sketch First in Putnam's Magazine - March 1854
Below, the digitized 1854 volume 3 of Putnam's Monthly Magazine courtesy of Hathi Trust Digital Library. Installments of Melville's "The Encantadas, or Enchanted Isles" appear in the March, April, and May issues.
Melville included "The Encantadas" in his 1856 book, the collection of magazine sketches titled The Piazza Tales. Here is how "Sketch First" looked there, from the California Digital Library via the Internet Archive, another great resource deserving of generous support: