Abraham Merritt's "The Moon Pool" (novelette, lost civilization, free)

While it didn't really work for me, there are well known sources that appear to hold a high opinion of this story:

1. Jim Baen's Universe, #16 (December 2008), includes it in its Classic section.
2. It's included in one of the Hartwell/Cramer anthologies (I think).
3. God in Eric Frank Russell's "Hobbyist" is too similar to the "dweller" in this story.
4. Strange affliction that is spreading through the countryside in Kono Tensei's "Hikari" affects people in ways somewhat similar to the way the branded (by "dweller") human's affected skin behaves in this story.

Story summary.

Dr David Throckmartin led an expedition to the "island of Ponape in the Carolines" somewhere in the Pacific. The island is part of a chain. Chain has ancient ruins considered haunted by "great spirits—ani—who were particularly powerful when the moon was at the full". Locals avoid the ruins - even more so during the nights of full moon. Expedition included David's wife Edith, his assistant Dr Charles Stanton, & "a Swedish woman, Thora Helversen, who had been Edith Throckmartin’s nurse in babyhood".

Their adventure will lead to discovery of an ancient elder race "that blossomed ages before the seeds of Egypt were sown". All four members of the expedition will be lost.

Fact sheet.

First published: All-Story Weekly, 22 July 1919. (I've a feeling this magazine was one of the many names of Argosy during its long life, or at least related to it in some way. But am not sure.)
Rating: B.
Download full text from Gaslight.
Note: This post is based on a reading the version of the story that appeared in Jim Baen's Universe, #16 (December 2008), but this Gaslight version appears to be the same. There is a 6-times longer novel version at Project Gutenberg. G W Thomas has more to say on the history of this story & its novelization.