Figures of Earth by James Branch Cabell

Thereafter Count Manuel could not long remain away from the window through which Ruric had climbed with a lantern, and through which Ruric had returned insanely blaspheming against law and order.

The outlook from this window was somewhat curious. Through the two other windows of Ageus, set side by side with this one, and in appearance similar to it in all respects, the view remained always unchanged, and just such as it was from the third window so long as you looked through the thick clear glass. But when the third window of Ageus was opened, all the sunlit summer world that you had seen through the thick clear glass was gone quite away, and you looked out into a limitless gray twilight wherein not anything was certainly discernible, and the air smelt of spring. It was a curious experience for Count Manuel, thus to regard through the clear glass his prospering domains and all the rewards of his famous endeavors, and then find them vanished as soon as the third window was opened. It was curious, and very interesting; but such occurrences make people dubious about things in which, as everybody knows, it is wisdom's part to believe implicitly.