It was first published in July 1957 in Saturn magazine under the name The Murky Glass.
Fred Akeley inherits a house from his late cousin Wilbur Akeley, a scholar from Miskatonic University who was “a student of archaeology and anthropology”. Wilbur spent years overseas and his travels included visits to “Mongolia, Tibet, and Sinkiang Province” and “South and Central America, and the southwestern part of the United States”.
Fred Akeley moves into his inherited house, which has had a great circular window of cloudy glass installed as a gable window. Wilbur’s papers mention that the window has been made from special glass from “Leng… possibly Hyadean in origins”.
It transpires that the special window is a dimensional portal, connecting the house directly across space and time to the vistas it shows.
Behind the Mythos
As detailed in the posthumous collaboration controversy article, Derleth took several tiny story ideas or the briefest of notes, wrote stories related to them or somehow inspired by them, and used Lovecraft's name on them. These are not Lovecraft stories, albeit they are indeed Mythos stories.