It was a feather whose vanes were fused into a sharp, glassy membrane.

Aqueducts laced the planet like the ribs on a basketball, meeting at ocean-sized black pools covered with glassy membranes.

I coated my sclera with a hard and glassy membrane, and, unblinking, I stalked home with my supplies through a fierce and growing wind.

The thin glassy membrane of both wings, especially the larger left wing, functions as a diaphragm or drumhead to amplify the sound that is produced when the file is moved over the scraper.