. Encyclopaedia : or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of systems ... . as as ftrongly magnetic as if it had been touch-ed by a pawerful loadftone. The place where he be-gan to rub was always the north pole. In thefe ex-periments it fometimes happened that the virtue wasimparted by a few ftrokes, nay, by a fingle one, afmall needle was made to receive a very conliderablepower. Thus he imparted^ to two compafs needlesfuch a degree of magnetic power, that
. Encyclopaedia : or, A dictionary of arts, sciences, and miscellaneous literature; constructed on a plan, by which the different sciences and arts are digested into the form of distinct treatises of systems ... . as as ftrongly magnetic as if it had been touch-ed by a pawerful loadftone. The place where he be-gan to rub was always the north pole. In thefe ex-periments it fometimes happened that the virtue wasimparted by a few ftrokes, nay, by a fingle one, afmall needle was made to receive a very conliderablepower. Thus he imparted^ to two compafs needlesfuch a degree of magnetic power, that one took and another a whole ounce of iron; and thoughthefe needles were anointed with linfeed-oil to keepthem from ruffing, and a hard coat was thus formedupon them they neverthelefs retained their alfo a knife was made fo ftrongly magnetical,that it would take up an ounce and three quarters ofiron. Four fmall pieces of fteel, each an inch longand TTth of an inch broad, as thin as the -fpring of awatch, were thus impregnated with the magnetic vir-tue, and then joined into a fmall artificial magnet;which at its firft formation took up eight times its owa Magnetism Plate CCLXXV1 ^ 3 9fc*. S. Ill/mfnv /r. Chap. III. MAGNETISM. rradlicc. own weight of iron ; and after being fix years kept in * the moil carelefs manner, was found to have rather gained than loll any thing of its virtue. In the courfeof his experiments, Mr Marcel found, that the end atwhich he began to rub was always the north pole,whatever petition the fteel was laid in. On rubbing apiece of fleel from one end to the middle, and thenfrom the other end to the middle, it acquired twonorth poles, one at each end, the middle being a fouthpole. Beginning to rub from the middle towardseach end, he found a north pole in the middle and afouth pole at each extremity. Magneiifm may be communicated to a fmall piecePlate °f foft fteel in thefollowing manner. Take two ironcclvxxi bars of about an inch fquare
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