The effect of temperature on recctification has studied in the case of six different crystals. The effect of temperature variations on crystal rectification in the interval ~75 to + 30 ^oC is especially intresting in the cases of silicium and molbednite. In the former case there is a very marked increase in rectification at the higher temperature, and in the latter case the sign of the rectification is changed. The presence of a magnetic field appears to have no effect on rectification.