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The Queries were these.
1. Whether a Needle may be so toucht upon any Magnet, as not to point to the true North and South? &c.
2. Whether different Load-Stones, will give different directions? or, whether fainter or stronger touches, upon one and the same Magnet, will cause any Variation in the directions? &c.
To these the Industrious Mr. Sellers returns this Answer:
To the First; That he had often made tryal with many Needles touching them in each Hemisphere of the Stone, with all variety of wayes he could imagine, to find, if it were possible by that means to cause any of these Needles to vary in its direction but, that he alwayes found the contrary; all of them conforming to the Magnetical Meridian, and standing North and South, as other Needles, that were toucht upon the very Pole of the Stone. He adds, that some of these Experiments he tryed in London, when there was no Variation known.
To the Second; 1. That, upon frequent tryals of touching Needles upon different Load-Stones, of several bignesses, as also of different vertue; the several Needles, touched upon these different Stones, gave all of them the same directions. This he thinks is confirm'd by all the Needles and Sea-Compasses, made in several parts of the World, and consequently touched upon several Stones of several Countries, yet all agreeing in this Magnetical Harmony, that they all give the same directions. 2. That having sometimes drawn a Needle, only over the Pole of the Stone, within the Sphere of its vertue, without at all touching the Stone; it hath received the same directive quality from the Stone, as if it had been really toucht upon the Stone it self, though not altogether so strong, as if it had toucht the Stone. Again, that having toucht Needles upon the Stone, with faint strokes, and other Needles with stronger; all these Needles received the same effect from the Stone, both for strength and direction; he conceiving, that 'tis not the fainter or stronger touches upon the Stone, nor the multiplicity of Strokes, that varies the Needles strength or direction; but that the Nature of the Steel, whereof the Needle is made, and the Temper that is given
thereunto,
