Micrometer microscope signed by M. Meyerstein, German, mid 19th century with wooden base Micrometer microscope signed by M. Meyerstein 1831-1870
Rheostat, wooden board and metal fittings, by Gaiffe of Paris, early 20th century Rheostat, wooden board and metal fittings 1901-1930
"CDX" X-ray machine, wall-mounted model, by the Victor X-ray Corporation, USA, 1923-1928 "CDX" X-ray machine 1923-1928