Have been reading this adventure story, first published in 1919, on my Palm T|X over the last few weeks, really reminded of it by Charlie Stross' use of the phrase "moon pool" in The Jennifer Morgue. The plot is classic enough: on an isolated tropical island, the Moon Pool is in fact the gateway to an underground world where the struggle between the forces of good and evil (each led by a beautiful priestess) is resolved by the agency of our narrator and his chums.
The characters are utter clichés. The Scandinavian sea-captain is, in fact, a Viking; the Russian is villainous (apparently a German during first magazine publication); the priestesses are both beautiful and nearly nude at all times. Most striking of all is the central character, Larry O'Keefe, with whom both priestesses (and, pretty clearly, also the male narrator) fall deeply in love. He is supposedly an Irishman with strong American connections, but I bristled rather at the cod-Oirishness of his dialogue. The son of The O'Keefe of Coleraine (that well known haunt of the old Gaelic aristocracy), he reminisces at one point:
An’ once I saw an Annir Choille, a girl of the green people, flit like a shade of green fire through Carntogher woods, an’ once at Dunchraig I slept where the ashes of the Dun of Cormac MacConcobar are mixed with those of Cormac an’ Eilidh the Fair, all burned in the nine flames that sprang from the harping of Cravetheen, an’ I heard the echo of his dead harpings—Carntogher is real enough, and credibly reachable from Coleraine, but the Annir Choille, Dunchraig and Cravetheen are all taken from the works of Fiona MacLeod (real name William Sharp), at least in the first instance.
For all that, Merrit's descriptive prose has power, coherence, and energy, and you can see his influence on Lovecraft; the first few scenes after passing through the Moon Pool in particular are very reminiscent of Lovecraft's Land of Dream. There is still something a bit more visceral and twisted in Lovecraft's writing that I think makes him the superior craftsman, even though his prose is sometimes just a bit more over the top than Merritt's.