[Magnetism] Kircher, A. Magnes sive De Arte Magnetica Opus Tripartitum

Cologne, J. Kalcoven, 1643. 2nd ed. (28),797,(33),(5) p. Frontisp. w. double-headed eagle and a view of Cologne, sm. title vignette, 28 (of 29) copper engr. plates, 3 full-p. woodcuts and approx. 170 in-text woodcuts. Leather, orig. cased binding, gilt borders, gilt title on spine. Sm. 4to.

Ex libris. New endpapers, most text pages sl. browned/ foxed. In this work, Kircher pays special attention to magnetism, more specifically terrestrial magnetism. Other Jesuits of his time, such as Garzoni and Cabeo, also wrote on this subject. Kircher studies magnetic declination and its possible use to determine geographical longitudes. At the time, this was an important subject for long sea journeys. First, he collects a large number of observations on magnetic declination from different sources. Kircher proposes that a magnetic map could be made based on these observations, and he discusses the causes of declination and presents a model for the origin of the magnetic field of the Earth. Kircher finally considers magnetism as a cosmic force originating in God.