his error as to change of verticity, [73].
suspends iron upwards by a thread, [92].
his error as to centre of the orbe of virtue, [95].
his error as to the polarity which causes repulsion, [102].
his error as to magnetick opposing forces, [103].
experiment with a balance, [108].
his error as to iron being intoxicated, [138].
his error as to iron excited by a diamond, [143].
his error as to the pointing of a magnet, [144].
proportion between loadstone and iron, [149].