![](https://coimages.sciencemuseumgroup.org.uk/732/280/large_thumbnail_smg00450067.jpg)
![](https://coimages.sciencemuseumgroup.org.uk/732/280/large_thumbnail_smg00450067.jpg)
![](https://coimages.sciencemuseumgroup.org.uk/439/331/large_thumbnail_smg00206414.jpg)
Evershed's portable ohmmeter no.20818
![](https://coimages.sciencemuseumgroup.org.uk/443/962/large_thumbnail_smg00224313.jpg)
Evershed's Ohmmeter no.2
1889
![](https://coimages.sciencemuseumgroup.org.uk/444/7/large_thumbnail_smg00224363.jpg)
Evershed's portable Ohmeter no.399
![](https://coimages.sciencemuseumgroup.org.uk/521/192/large_thumbnail_smg00296342.jpg)
Evershed's portable Ohmeter
![](https://coimages.sciencemuseumgroup.org.uk/477/332/large_thumbnail_smg00246713.jpg)
direct reading insulation/resistance indicator
![](https://coimages.sciencemuseumgroup.org.uk/443/997/large_thumbnail_smg00224352.jpg)
Fixed coil moving needle ohmmeter
1881
![](https://coimages.sciencemuseumgroup.org.uk/333/237/large_thumbnail_smg00052020.jpg)
"Metrohm" moving coil ohmmeter for use with external battery
![](https://coimages.sciencemuseumgroup.org.uk/202/13/large_thumbnail_cd0622_010_100611_2010_21_ohmmeter_made_by_record_of_broadheath.jpg)
Ohmmeter made by Record of Broadheath. Used in the 1960s by James Alan Ridehalgh
1925-1935
![](https://coimages.sciencemuseumgroup.org.uk/478/304/large_thumbnail_smg00247825.jpg)
Evershed ohmmeter
circa 1905
Direct reading ohmmeter no. 23008 by Everett
1903
Ohmmeter with calibration chart
circa 1892