DESCRIPTION Early 20th century brass telescope diopter. Alidade composed of a flat rod, called rule, at the ends of which two pinnulae rise hinged; equipped with metric scale, compass, spirit level and distance metric collimator telescope. DETAILS Title: Telescope Diopter Brass Italy XX Century Period: 20th Century / 1901 - 2000 Year: Early 20th Century Origin: Italy Material: Glass, Brass Dimensions (cm/inches): Height: 15.5 cm (6.10'') Width: 46 cm (18.11'') Depth: 10 cm (3.94'') MPN Product Code: OGANOG0176743.