Keystone viewer Meadville retailer Pa. Pat’d April 12 1904

Product Name: Keystone viewer Meadville retailer Pa. Pat’d April 12 1904
The stereo viewer ! These were very popular in the late 19th century all the way up to World War One. They produced a 3-d image and were Vital retailer form of entertainment well before the day's television and even radio! They also provided culture and spread information and knowledge among the masses! A image was take from two slightly different angles. These images would be placed side by side on a card. Then the card was placed in the viewer. The person holding the viewer would adjust the card till it rendered the 3-d image! These are so fun I had this in my personal collection for quite a while! The condition is near mint I would say PERFECT! The logo is on the bottom with a patent date of 1904! This is about as nice as they come!.