A Stereo Viewer made by Underwood & Underwood of New York. Including a wooden handle and a stereoscopic picture. The viewer has two lenses at a set distance in an aluminum frame. The pictures can be moved horizontally in order to focus them. These devises became popular in the middle of the 19th century. This is a Holmes type stereoscope, named after its inventor, Oliver Wendell Holmes (1860). The viewer is marked on the visor 'Sun Sculpture Trade Mark', and on the underside of the wooden bar: ' Warranted Underwwod & Underwood Manufacturers New York Patent Apllied For'