Mercury ion engine, one of five
1978
illuminated moving scale indicator with transformer and operating switch
Model of the N.S. "Savannah" (1959)
1958-1965
Lawrence Scott ampmeter and voltmeter
Electrostatic voltmeter, disassembled to show parts
Crompton dead beat voltmeter no.12861 180-270v.
Whole rigged model of H.M.S. 'Himalaya'
1850-1854
Wire wound potentiometer
1910-1940