Abstract
An account is given of experiments performed to investigate the possibility of applying electrical methods to the measurement of humidity. Two methods are considered, depending on (1) the change in resistance of organic materials (cotton-wool and human hair) on exposure to water vapour; (2) the change in mobility of ions due to water vapour.
Results show that in the first case the change in resistance with humidity is not linear, the logarithm of resistance being proportional to the humidity, while in the second the effect produced is too small to permit of accurate measurement. Thus, in neither case does the method seem suitable for general use, though each could be applied in special cases.