On the Magnet, by William Gilbert

Chap. xi.

Parallels.

I n parallel circles the same strength and equal power are perceived everywhere, when various magneticks are placed on one and the same parallel either on the earth or on a terrella. For they are distant from the poles by equal intervals and have equal tendencies of declination, and they are attracted and held, and they come together with like forces; just as those regions which are situated under the same parallel, even if they differ in longitude, yet we say possess the same quantity of daylight and a climate equally tempered.

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Last updated Friday, March 14, 2014 at 22:17