Charles Wheatstone (1802-1875) published his paper "On some remarkable, and hitherto unobserved, Phenomena of Binocular vision" in the Philosophical Transactions of the Royal Society of London in 1838. In it he shows how two drawings of the same object made with slightly different vanishing points will look three-dimensional when each drawing is viewed simultaneously and individually by the right and left eyes. This requires the use of stereoscopic viewers, a number of which are shown on this page. After the invention of photography in 1839 it was possible to use photographs instead of drawings.
The viewer below, shown in two different views, is in the
Garland Collection of Classic Physics Apparatus at Vanderbilt University.
With the hatch at the top closed, it was used to view stereoscopic transparencies,
either on glass on on tissue paper. With the hatch open, standard 7" by
3.5" stereo cards could be viewed by reflected light.
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Two more combination positive/negative stereoscopic viewers. The one at the left is from the Wileman Collection of Optical Toys at the North Carolina School of Science and Mathematics in Durham; on the right is one at Middlebury College in Vermont.
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In this box-type stereo viewer, the individual eyepieces
may be adjusted individually for focus.
This viewer is in the Wileman Collection. |
| This is a "Sweetheart" stereoscopic viewer that allows
two people to view stereo positives at the same time. The card views are
loaded onto a rotating holder so that a number of cards could be viewed,
one after another.
One of the cards being examined is a stereoscopic picture of the moon by Lewis Rutherfurd, a lawyer and astronomer from New York City who also worked with early diffraction grating ruling engines. See: Thomas B. Greenslade, Jr., "The First Stereoscopic Pictures of the Moon", Amer. J. Phys., 40, 536-540 (1972) The device is in the Wileman Collection of Optical Toys at the North Carolina School of Science and Mathematics. |
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This folding viewer for individual stereoscopic pictures
has a cut-out between the lenses to accommodate the nose of the user!
The original folding viewer was patented by J. F. Mascher of Philadelphia in March 1853 and was designed to hold stereoscopic portraits using the daguerreotype process.. Unfortunately, this was at the very end of the daguerreotype era, and originals are quite rare. The example in my own collection does not show the stereoscopic effect very well. |
| The combination viewer, made in Paris, can be used to view either stereo cards or single positive prints. It is in the Wileman collection at the North Carolina School of Science and Mathematics. |  |
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Here is the classic stereo viewer of the type designed
by Oliver Wendell Holmes (1809-1894) ca. 1855. Since the 3-inch square
photographs are slightly too close for comfortable viewing, positive lenses
are supplied to make the user somewhat nearsighted. Since the lines of
sight from the two images are supposed to converge between the eyes, the
lenses are wedge-shaped to make the images appear to be located farther
apart.
Holmes should not be confused with his son, also Oliver Wendell Holmes (1841-1935), the Associate Justice of the United States Supreme Court. The viewer is in the Greenslade Collection, and the stereo card was made by him. |
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In 1928 the firm of Adam Hilger of London published a
"a series of stereoscopic photographs of Crystal Models edited by Sir William
Bragg and Prof. W.L. Bragg." There was also three stereoscopic photographs
of "Dr. Müller's X-Ray Spectrograph, as set up for the Debye Powder
Method" and one of "The Ionisation Spectrometer" that appears to be Bragg
apparatus.
The glossy stereoscopic pairs are 8.5 cm by 11.5 cm, and there are thirty eight of them. They form part of the Greenslade Collection. |
REF: Thomas B. Greenslade, Jr. and Merritt W. Green, III, Experiments with Stereoscopic Images", The Physics Teacher, 11, 215-221 (1973)
