The Natural Philosophy of William Gilbert and His Predecessors

by W. James King

[74] M: p. 62.

[75] M: p. 63.

[76] M: p. 60.

[77] M: pp. 19, 21, 43, 53, 61, 63, 184.

[78] M: p. 61.

[79] M: pp. 66, 67.

[80] M: p. 69. Gilbert is confusing Aristotelian matter and an element. He includes cold and dry, with formless and inert! See also Maier, op. cit. ([footnote 17]).

[81] M: p. 63; bk. 1, ch. 17.

[82] M: pp. 67, 181-183, 235-240, 281-289, 313-314.

[83] M: p. 71. See also pp. 314 and 331. It is not clear, at this point, whether he believed a "properly balanced" terrella would be a perpetuum mobile.