English: Fourth order Fresnel lense in situ in the Elizabeth Donkin lighthouse, Port Elizabeth, South Africa. The lighthouse was built in 1903 replacing an earlier wooden structure and decommissioned in 1973.[1] The lighthouse balcony is 21.6 m above ground level and 75.6 m about sea level. The glasses on the lower support give an indication of the size of the lens.
This media shows a South African Protected Site with SAHRA file reference 9/2/073/0005.
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This image has been assessed under the valued image criteria and is considered the most valued image on Commons within the scope: Fresnel Lens, Elizabeth Donkin Lighthouse, Port Elizabeth, South Africa. You can see its nomination here.
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