Sound: A Course of Eight Lectures

A detailed landscape engraving shows a large fog siren positioned on a grassy cliffside overlooking the sea. The machine features a massive, cone-shaped acoustic horn mounted on a wooden frame with wheels. Behind the horn is a complex mechanical assembly including pipes, valves, and a vertical steam boiler or chimney. In the background, the coastline curves away with steep white cliffs. A small figure of a person stands on the slope near the machine to provide a sense of scale. The sea is visible to the left with a small sailing vessel on the horizon.

original: "Fog-Syren"

Fog Siren: A powerful instrument used for maritime signaling. It typically uses a steam whistle and a large acoustic horn to warn ships during heavy fog. This was a major advancement in lighthouse technology during the nineteenth century.