C S Rolls in his 100 hp Mors Racer, 1904.

Steel seton clamp, 17th century.

A 'merkhet', Egypt, c 600 BC. Replica. Comp

Solid-state rectifier from the Philips Million-Volt Accelerator, 1937.

Conductor from the Philips Million-Volt Accelerator, 1937.

Steam recording meter from dynamometer Car

Baker-Brown's cautery clamps, French, 1841-1900.

Byzantine bronze weights, c 600-699 AD.

Open University pH meter and probe, 1990-1996.

Precision sound level meter, 1960-1979.

Open University pH meter and probe, 1990-1996.

pH meter, 1950-1970.