Magnetic Compasses and Chinese Architectures

In this paper, we are discussing the effect of the use of magnetic compasses on the orientation of ancient Chinese architectonical complexes. As Czech researchers proposed in 2011, assuming these complexes ideally oriented by the ancient architects along north-south direction, in the case that the surveys were made by means of magnetic compasses, we can find the axes of the complexes deviating from the cardinal direction, according to the local magnetic declination that existed at the time the structures were built. Following this idea, here we discuss some examples of possible alignments obtained by means of magnetic compasses, concluding that the Chinese surveyors adopted, during the Ming dynasty, a method based on the magnetic compasses. The architects of the antecedent Yuan Dynasty probably used an astronomical method.