The Weston cell as a house standard of e.m.f.

In its stability, accuracy, sensitivity to perturbations and mechanical robustness, the Weston cell is a good example of how a standard should not behave. However, with suitable temperature control and precautions against parasitic e.m.f.s, the Weston cell, for all its disadvantages, shows the best long-term stability, and can make a reliable house standard of e.m.f.