A set of painted glass discs are rotated via the small keyboard.

A neatly cut glass disc had been fitted into either end of the tube.

At any rate, Berliner found that trying to photoengrave the surface of a glass disc was fraught with problems.

The mechanical speaking clock used rotating glass discs where different parts of the time were recorded on the disc.

It traced a clear sound-modulated spiral line through a thin black coating on a glass disc.

The most significant exhibit is one of the original mechanical speaking clocks, made with rotating glass discs.

Nebogipfel led me now to the edge of our glass disc.

There was a round glass disc on one face, and a couple of levers on one side.

Heat is applied to a glass disc and its surrounding steel ring, causing a fusion of the materials.

It covered him from head to toe, with tinted glass discs for his eyes.