Jonkers. Earth’s Magnetism in the Age of Sail (2003). 166.
584
Helmont & Charleton. A Ternary of Paradoxes (1649). 40, 41; Fletcher & Fletcher. Athanasius Kircher (2011). 150; Thorndike. A History of Magic and Experimental Science (1923). Vol. 2. 310, 311.