A treatise of artificial magnets ; in which is shewn an easy and expeditious method of making them, superior to the best natural ones, and also, a way of improving the natural ones, and of changing or converting their poles : Directions are likewise given for making the mariner's needles. In the best form, and for touching them most advantageously, &c / by J. Michell.

  • John Michell
Date:
1750
Catalogue details

Licence: Public Domain Mark

Credit: A treatise of artificial magnets ; in which is shewn an easy and expeditious method of making them, superior to the best natural ones, and also, a way of improving the natural ones, and of changing or converting their poles : Directions are likewise given for making the mariner's needles. In the best form, and for touching them most advantageously, &c / by J. Michell. Source: Wellcome Collection.

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    brought too near, provided they do not touch, which they mud by no means do: it will be convenient to place between them a little bit of Wood, or any other Material, except Iron, to keep them at their diftance. The three Mag¬ nets in C D, (for fo we may properly enough call them, though their power as yet may be very fmall,) have all their South Poles down¬ ward, and placed towards the unmarked ends of the bars in the line, which are to be North Poles; and the three Magnets in EF, have all their North Poles downward and thefe are olaced towards the marked ends of the bars, which are to be South Poles. [As in C D, E F, the marks upon the flat fide of the Mag¬ nets are hid in feveral of them, there are little dots made on the edges, to diftinguifli the South Poles by, in the figure.] Thefe fix Mag- netical bars being thus placed. Aide them back¬ ward and forward three or four times the whole length of the line ; then remove the two end- moil: bars of the line into the middle, as be¬ fore, and Aide the Magnetical bars over them again ; then turn the bars in the line, the other fide upward, and go over them again, in the fame manner,excepting the endmofl: bars; which, when thofe in the middle are touched, are to be removed thither, to be touched in their turn.