The J. Paul Getty Museum
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The J. Paul Getty Museum: image dedicated to the public domain under Creative Commons Zero (CC0), stated on the media record itself ('Rights for Media'), with download clearance.
Carleton Watkins. Clay St. Hill R.R., San Francisco, Cal. Run by A.S. Hallide's patent Endless Steel Wire Rope and Gripping Attachment..., about 1874. The J. Paul Getty Museum.