PointReyesLighthouseOld

Here's the old lighthouse itself. The fresnel lens (which you can see in the window) turned around the actual light. The lens split the light into 24 vertical beams, and if you were out in a boat a beam would pass you every 6 seconds. Every lighthouse has a different rotational speed so you could tell which one you are near by timing the light.

Fresnel is pronounced 'freh-nel'.

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