100-inch mirror, loaded on a truck, nearing Mount Wilson Observatory. The mirror is covered with a tarpaulin. A small crowd of people surrounds the mirror and truck; five unidentified women follow the truck and four unidentified men either ride on the truck or walk beside it. The dirt road leads to Mount Wilson Observatory. Trees are seen along the sides of the road. Image courtesy of the Observatories of the Carnegie Institution for Science Collection at the Huntington Library, San Marino, California.