multi-prism spectroscope

John Browning, London
The spectroscope is constructed from lacquered brass and is supported by a three-legged base. It features six dispersing prisms housed within a brass circular, double frame, mounted on brass fixtures that rest on an opaque, circular glass plate. In addition to the six dispersion prisms, there are three movable Porro prisms. These can be adjusted to allow the light beam to pass through the dispersion prisms multiple times. The instrument comes with its original dove-tailed wooden box, measuring 35 x 37.5 x 40 cm. Signed by John Browning, London, circa 1885.

For more details on this instrument, see MM Instruments.

collection Mark McElyea