30/10/2026
Friday lighthouse fact💡
On 25 July 1823, a new kind of lens was tested at Cordouan Lighthouse on France’s Atlantic coast. Designed by Augustin Fresnel, its rings of glass focused the lamp’s light into a powerful beam that sailors could see from farther away.
It was the first test of a Fresnel lens in a working lighthouse.
Source: https://www.phare-de-cordouan.fr/mediatheque/