Binocular spectroscope apparatus by Spencer and Son, Dublin, 1874. Two parallel spectroscopes each with a prism in wooden mount), in a wooden case. The spectroscope was taken by the Transit of Venus Expedition to the Cape of Good Hope in 1874-75. It is probably unique. Binocular spectroscope apparatus with case
Wooden case for binocular spectroscope apparatus by Spencer and Son, Dublin, 1874. Wooden case for binocular spectroscope apparatus by Spencer and Son