"Large Prism By Pellin, C. 1900"
Large model of a Nicol prism mounted in a tube and placed on a brass support. The instrument is signed "Ph. & F. Pellin M[ais]on Duboscq Paris", therefore datable to around 1900. The prism measures approximately 14.5 cm in length and the brass tube 19.5 cm. The total height of the instrument is approximately 36 cm. This polarizing device was certainly used with a magic lantern for projection experiments. The condition of the prism appears to be excellent. Rare. 
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