Browse Items (3473 total)

Leslie's differential thermometer. Double bulbs on ends of a tube set into delicate wooden base. One bulb blue, one clear; liquid (blue) broken column. Faded mark on underside base showing existence of rectangular label.

cylindrical box with "Atwood's Replace Riders" written on top. Inside contains 15 metal slides of varying size with a hole punched in each of them.

With separate closing end. 5 coils per leg. Brass terminals. Combination typical of early to mid 19th century coils.

The curved vanes have been calculated to give straight-line tuning across the dial. Behind the dial, a travelling pointer illuminated by two small bulbs can be swept around to tune in to the stations. 2 (?) gangs of closely spaced vanes. Hand…

Bulls-eye lens with ball and socket joints at either end of stand rod. For illumination of microscope specimens.

Brass pump with T handle; detached end piece. With leather washers.

Circular magnifying lens on brass stand. Can rotate and can be extended in height.

2 string (wire) sonometer with screw tension. Dovetailed box with 4 sets of ornate slots between bridges. Later addition of small brass pulley on one end and brass hook on other to take wire with weights. Probably purchased by Prof Thomson.

Flat magnetic strip on tripod stand through which an axial current can be passed. Rotation takes place because of the force between the current and the permanent field of the magnet. The first primitive electromagnetic motor ( Faraday ) but a…