Air"; and it is perhaps worth our while to go back a little and glance over the coming of this current into the modern world. Having grown steadily through the Middle Ages, it appeared in full strength at the Reformation period; and in the sixteenth century Olaus Magnus, Archbishop of Upsala and Primate of Sweden, in his great work on the northern nations, declares it a well-established fact that cities and harvests may be saved from lightning by the ringing of bells and the burning of consecrated incense, accompanied by prayers; and he cautions his readers that the workings of the thunderbolt are rather to be marvelled at than inquired into. Even as late as 1673 the Franciscan professor Lealus, in Italy, in a schoolbook which was received with great applause in his region, taught unhesitatingly the agency of demons in storms, and the power of bells over them, as well as the portentousness of comets and the movement of the heavens by angels. He dwells especially, too, upon the perfect protection afforded by the waxen Agnus Dei. How strong this current was, and how difficult even for philosophical minds to oppose, is shown by the fact that both Descartes and Francis Bacon speak of it with respect, admitting the fact, and suggesting very mildly that the bells may accomplish this purpose by the concussion of the air.(246) (245) For Elector of Saxony, see Peuchen, Disp. circa tempestates, Jena, 1697. For the Protestant theory of bells, see, e. g., the Ciciones Selectae of Superintendent Conrad Dieterich (cited by Peuchen, Disp. circa tempestates). For Protestant ringing of bells to dispel tempests, see Schwimmer, Physicalische Luftfragen, 1692 (cited by Peuchen, as above). He pictures the whole population of a Thuringinian district flocking to the churches on the approach of a storm.