1926 The Strange High House in the Mist

Weird Tales 1931.10
Written 1926.11, published in Weird Tales 1931.10.

Opening Statement:
     In the morning, mist comes up from the sea by the cliffs beyond Kingsport. White and feathery it comes from the deep to its brothers the clouds, full of dreams of dank pastures and caves of leviathan. And later, in still summer rains on the steep roofs of poets, the clouds scatter bits of those dreams, that men shall not live without rumor of old strange secrets, and wonders that planets tell planets alone in the night. When tales fly thick in the grottoes of tritons, and conchs in seaweed cities blow wild tunes learned from the Elder Ones, then great eager mists flock to heaven laden with lore, and oceanward eyes on tile rocks see only a mystic whiteness, as if the cliff's rim were the rim of all earth, and the solemn bells of buoys tolled free in the ether of faery. 
What in Brown Jenkin's Name..?
     A man is curious about a house which has its front door facing the void beyond the edge of a cliff. He eventually takes a journey with its ancient occupant.
Synopsis:
     On top of a foreboding cliff sits an ancient house. It’s occupant seems to have remained the same over many centuries (even as observed by the preternaturally-aged "Terrible Old Man"). A philosopher named Olney arrives in nearby Kingsport at the foot of the cliff and hears rumors of lightning coming from the high house, and of "flapping" visitors. He finds his way to the house (from the Arkham side) and notes that the front door leads directly to the void beyond the cliff edge. Eventually, the bearded home owner arrives (seemingly from the cliff-side) and invites Olney in. He tells Olney stories about ancient beings including the Elder Ones, Atlantis, ocean floor “blasphemies”, Nodens and “other gods”. Eventually Neptune and some other sea beings arrive and spirit the two of them away. Later, Olney returns to Kingsport, a somewhat changed man (missing something, according to the Terrible Old Man). The townspeople dread the return of the people of Kadath to the cliff.  
Essential Saltes:
     And the day wore on, and still Olney listened to rumors of old times and far places, and heard how the kings of Atlantis fought with the slippery blasphemies that wriggled out of rifts in ocean's floor, and how the pillared and weedy temple of Poseidon is still glimpsed at midnight by lost ships, who knew by its sight that they are lost. Years of the Titans were recalled, but the host grew timid when he spoke of the dim first age of chaos before the gods or even the Elder Ones were born, and when the other gods came to dance on the peak of Hatheg-Kia in the stony desert near Ulthar, beyond the River Skai. 
From Dr. Armitage's Notes:
The Horrible Conclusion:
     All these things, however, the Elder Ones only may decide; and meanwhile the morning mist still comes up by that lovely vertiginous peak with the steep ancient house, that gray, low-eaved house where none is seen but where evening brings furtive lights while the north wind tells of strange revels. White and feathery it comes from the deep to its brothers the clouds, full of dreams of dank pastures and caves of leviathan. And when tales fly thick in the grottoes of tritons, and conchs in seaweed cities blow wild tunes learned from the Elder Ones, then great eager vapors flock to heaven laden with lore; and Kingsport, nestling uneasy in its lesser cliffs below that awesome hanging sentinel of rock, sees oceanward only a mystic whiteness, as if the cliff's rim were the rim of all earth, and the solemn bells of the buoys tolled free in the ether of faery.
Read it here.

Follow'd by "The Dream Quest of Unknown Kadath"