Pair of Clark standard cells in one case
Profs. Ayrton and Perry standard inductance
Clark standard element (cell) no. 142
1872
Clark standard cell
Electrically maintained tuning fork, by Muirhead
Standard resistor no. 4644
Standard air capacitor
Pair of Clark standard cells in one case
1/3 microfarad standard condenser
1892
Clark standard cell no. 1297 by Nalder Brothers and Co.
Standard condenser no. 30510
1911
Pair of turned wooden standards
1880-1920