DOUBLE REFRACTION APPARATUS
FRENCH, 19TH CENTURY
signed M.on. Jules Duboscq Ph Pellin Paris, screw mechanism for rotating disc 0-180-0 with vernier, hinged on compass joint on lacquered brass column on cast iron tripod case, marked with O.3.
20in. (49cm.) high
DOUBLE REFRACTION APPARATUS
FRENCH, 19TH CENTURY
signed M.on. Jules Duboscq Ph Pellin Paris, screw mechanism for rotating disc 0-180-0 with vernier, hinged on compass joint on lacquered brass column on cast iron tripod case, marked with O.3.
20in. (49cm.) high