<p>Glass pieces make up the lens. The glass pieces are prism shaped and help amplify the light so it can be seen further.</p>
<p>A third-order Fresnel lens reflected the first light. The fixed white beam could be seen 17 miles out on Lake Superior. The lighthouse became fully automated in 1958 and transferred from the Coast Guard to the National Park Service in 1968.</p>
<ul><li>Keywords: Pictured Rocks National Lakeshore; Pictured Rocks; piro; Au Sable Light Station; au sable; lighthouse; lake superior</li></ul>
NPS Photo
Taken on 2 August 2018
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