HIGGINS' AUTOMATIC DUPLEX FINDER
John J. Higgins, New York City 1888? - 1893
The Automatic Duplex Finder was an early camera viewfinder, patented by John J. Higgins of New York City on July 12, 1887, Patent No. 366,584. The unit measures 4" x 3" x 2". It functioned simply by rotating the viewer upside down. In one position, the internal mirror falls into a 45 degree position, permitting a waist-level view from the top. Rotating it once more causes the mirror to fall flat, permitting an eye-level view from the rear.
It's size is considerably larger than finders found on self-casing cameras of the 1890's although it could be used with any camera, simply by resting it on the camera's body. Its introduction, prior to the emergence of most self-casing cameras, suggests it was more intended for field camera use. This particular example has no mounting hardware, or evidence that it was ever mounted on a camera. However, the patent's wording states that the finder could be mounted, or be removable in use. An Internet search revealed a 2011 eBay auction, where an Eastman dry plate camera was equipped with a Higgins Automatic Duplex Finder.
The granting of Higgins' patent is mentioned in the August 6, 1887 issue of the Scientific American. Mention was also made in a November 1887 article in The Photographer's World, stating that a "Dr. J.J. Higgins" has "produced a model of his own invention". It was sold by George Murphy as "The Higgins Patent Duplex Finder" in the 1890 issue of Photographic Mosaics, and it also appears in G. Gennert's 1893 Catalogue as the "Automatic Duplex Finder". Higgins also held at least five other photographic patents, one for a detective camera under Patent No. 371,458 dated October 11, 1887. It was designed to have interchangeable body sections that permitted lenses to be easily changed, or to store plate holders separate from the camera.
With only a few having been seen, one can assume that production of the Automatic Duplex Finder was very limited over an estimated 6-year period. You're not likely to come across one soon, but I have no doubt that other examples exist.