According to Kinbote (in VN’s novel Pale Fire, 1962, Shade’s mad commentator who imagines that he is Charles the Beloved, the last self-exiled king of Zembla), the eye of the mind sees Gradus, and the muscles of the mind feel him, as always streaking across the sky with black traveling bag in one hand and loosely folded umbrella in the other, in a sustained glide high over sea and land:
Lines 131-132: I was the shadow of the waxwing slain by feigned remoteness in the windowpane.