The feeling of chi may be realized when one is in an extremely peaceful mind state. According to the chikong literature and field surveys, the best time to sense the feeling of chi is between 1 and 5 am. As a part of an extensive investigation of chikong, geophysicists in Taiwan looked for a method to interpret the geomagnetic effect on the time-selecting concept. In this article, we propose the application of a time-domain archaeological method to this problem. We study the geomagnetic effect by investigating time-selecting behaviour through ancient literature and recent data combined with a field survey of geomagnetic time variation.