Browse Items (3473 total)

One of two 60 degree glass prisms with beveled edges and 3 frosted faces including the base. A small capital B has been written on one frosted side in pencil near the base; labelled as small with reference to the counterpart larger prism b

Wooden box with tube and lens form one end and "bellows" with a rectangular opening at the other. Turning wheel that opens and shuts aperture on side of box and handle to slide lens back and forth on tube with mm scale underneath marked every 5 mm…

With 6 concentric inner conductors and 12 iron sheathing wires. Short section held in brass band.

Telescopic level, all brass on adjusting table with 4 screwed feet. Is this the item in the 1823 inventory ' leveling instrument, Miller Edinburgh pounds 6.16.6 ' (C501?).

A brass stand with a large circular metal lens holder attached. Lens included.

Wooden beam with two sliding lenses on it, assumed for use with part a of set. One lens is in a brass frame. Set up as a telescope arrangement

Rectangular mirror in wooden frame curving inwards. Brass plate on back with engraving on it.

Searchlight case on tripod stand. The mirror formerly within is stored separately. This device was used in the 1960s by the Natural Philosophy Radio Astronnomy group as the base for a 2 m diameter, 9 mm wavelength, steerable radio reception dish. …

cylinder with screw hole on top of wooden base with groove for running along optical bench.

Set of 24 brass slides with different sized apertures cut from them and painted black. In grooves in a wooden block.