Henri Lehon en de zondvloedtheorie van J. Adhémar

Abstract

Henri Lehon and the diluvial theory of J. Adhemar In 1842 the French mathematician Joseph Adhemar published a remarkable theory on the causes of the deluges that played a prominent role in geology. He believed that as a consequence of the precession of the equinoxes, and the resulting difference between the lengths of the seasons, the northern and the southern hemisphere would be alternatively immersed by the world oceans, floating towards the coldest pole of the planet. This periodical movement was marked by a global catastrophe when the slowly melting pole suddenly collapsed. Adhemar's theory was taken up in Belgium by the geologist Henri Lehon, who succeeded in combining the theory with the stratigraphical views of d'Orbigny and Hebert. Lehon strongly opposed the orogenetical school of Elie de Beaumont, at least with regard to the more recent geological periods. Later, however, Lehon weakened his position under the influence of the work of Lyell and Croll. Adhemar's theory now played only a minor role in the explanation of the great Ice Age, while its catastrophical aspects disappeared out of view.