[photo-3d] Re: help ID an unusual old viewer?

[abram.klooswyk@xxxxxx]

Peter Abrahams: 
>... intriguing binocular viewer for sale...
>It is estimated to be late 19th century & British; of brass, 
>4 inches wide, with two greenish glass right angle prisms 
>whose angle to each other is adjustable & fixable by the 
>central mechanism.  It produces side-by-side images which are 
>reversed, i.e. left to right and right to left. In addition 
>the viewer reverses writing so that it runs backwards right to left.

As Ben Melton wrote, this is a pseudoscope, which follows from the 
optical description. 
The other day, in a terminology discussion which you justly skipped 
:-), I have mentioned that Wheatstone has invented the instrument, 
his 1852 reading has two figures illustrating it.
(A reprint of that paper is in: Nicholas J. Wade "Brewster and 
Wheatstone on Vision" , Academic Press, London 1983 - 
unfortunately out of print, but in many libraries) 

Peter, are you sure it is late 19th century and not early 
20th? For pseudoscopes have been produced to view stereo x-
rays, any size, I have such a viewer from more recent date
which is called a Stereobinokel (It's German). 
(First stereo x-ray 1896, I believe you have that year in the 
information on your site, first pseudoscope made for viewing
x-rays - ?.) 

Abram Klooswyk



 

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