The British Refracting Unit, No 1652
 Catalogue Number: 1123 The British Refracting Unit, No 1652 Category: Equipment Sub-Category: Refractor Phoropter Phorometer Year Of Publication/Manufacture: c1933 Time Period: 1900 to 1939 Place Of Publication/Manufacture: Croydon, England Publisher/Manufacturer: Ellis Optical Co Description Of Item: Black metal instrument for measuring refractive error and binocular functions with stem for suspension arm mounting. Multiple lenses; spheres +18 to -9.00 DS, cyls to -3.75 DC. Variable prisms (Risley & Stephens Phorometer). Jackson's cross cylinders mounted in front. Horizontal spirit level. Imprinted on the front face: The British Refracting Unit No 1652 and the right, Patent Nos 402516, 402876m 403661 on the left and on the base of the PD adjustment 'Ellis Optical Company England' W: 28.0 cm x H: 33.0cm x D: 12.0 cm Condition: Good, paintwork worn Location: Archive room. West wall. Unit 3 Drawer 4 |