Colocation | Broadband Wireless | Dedicated Servers | Web ...

A calcite prism in the lower tube causes a doubling of the image. A 'double prism' of flint glass achromatizes the beam. Interocular distance is adjutable by a rack & pinion. (RMS Accession no.: 1970-101/part, also marked RMS no. 54, Turner catalogue 416, Inventory no. 91539) ................
................