. 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 ... . My. zz JYp- .Yrn//i S,-nf7t .1,7////F>,rrAv/7a / Z/affa/tCA ? /r. Chap. IV. MAGNETISM. Plate CCLXXVIII, Entertain- nately go into fimilar holes made in the bottom of theing Experi- ]arge box. In each of thefe tablets is to be placed afmall magnetic ball and their poles are to be difyofedas expreifed in the figure. Cover each of thefe tabletswith a thin plate of one of the fix
. 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 ... . My. zz JYp- .Yrn//i S,-nf7t .1,7////F>,rrAv/7a / Z/affa/tCA ? /r. Chap. IV. MAGNETISM. Plate CCLXXVIII, Entertain- nately go into fimilar holes made in the bottom of theing Experi- ]arge box. In each of thefe tablets is to be placed afmall magnetic ball and their poles are to be difyofedas expreifed in the figure. Cover each of thefe tabletswith a thin plate of one of the fix following metals,viz. gold, filver, copper, iron, pewter, and lead. Youmuft alfo have a magnetic perfpective, at the end ofwhich is to be two circles, one divided into fix equalparts, and the other into foar, as in fig. 37. from thecentre of which there muft be drawn an index N,whofe point is to be placed to the north. Therefore,when yon are on the fide CD of the box, and holdyour perfpeclive over any one of the tablets that areplaced on the holes E, F, G, fo that the index drawnon the circle is perpendicular to the fide AB, theneedle in the perfpeclive will have its fouth pole di-rected to the latter that denotes the m
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