We found in a former investigation that by measuring sleep parameters, the REM latency is shortened in the E-W position of sleepers compared with the N-S position. This paper reports on a further neurological observation in humans concerning the influence of the earth's magnetic field: there are statistically significant differences in the EEG of normal subjects, depending on whether the subjects sit facing the N-S or E-W direction. The difference is especially pronounced in the alpha-power.