![](https://coimages.sciencemuseumgroup.org.uk/425/764/large_thumbnail_smg00225133.jpg)
![](https://coimages.sciencemuseumgroup.org.uk/425/764/large_thumbnail_smg00225133.jpg)
![](https://coimages.sciencemuseumgroup.org.uk/424/532/large_thumbnail_smg00225096.jpg)
Pair of Clark standard cells in one case
![](https://coimages.sciencemuseumgroup.org.uk/467/295/large_thumbnail_smg00225105.jpg)
Profs. Ayrton and Perry standard inductance
![](https://coimages.sciencemuseumgroup.org.uk/424/516/large_thumbnail_smg00224896.jpg)
Clark standard element (cell) no. 142
1872
![](https://coimages.sciencemuseumgroup.org.uk/424/531/large_thumbnail_smg00225095.jpg)
Clark standard cell
![](https://coimages.sciencemuseumgroup.org.uk/424/692/large_thumbnail_smg00080568.jpg)
Electrically maintained tuning fork, by Muirhead
![](https://coimages.sciencemuseumgroup.org.uk/424/526/large_thumbnail_smg00225075.jpg)
Standard resistor no. 4644
![](https://coimages.sciencemuseumgroup.org.uk/367/660/large_thumbnail_smg00181754.jpg)
Standard air capacitor
![](https://coimages.sciencemuseumgroup.org.uk/424/534/large_thumbnail_smg00225098.jpg)
Pair of Clark standard cells in one case
![](https://coimages.sciencemuseumgroup.org.uk/423/425/large_thumbnail_smg00224935.jpg)
1/3 microfarad standard condenser
1892
![](https://coimages.sciencemuseumgroup.org.uk/424/530/large_thumbnail_smg00225094.jpg)
Clark standard cell no. 1297 by Nalder Brothers and Co.
![](https://coimages.sciencemuseumgroup.org.uk/423/397/large_thumbnail_smg00224827.jpg)
Standard condenser no. 30510
1911
Pair of turned wooden standards
1880-1920