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had also seen him put in practice. And that Mr. Canton had moreover changed in his presence the poles of a natural loadstone, by placing it in an inverted direction, between the contrary poles of two of his large bars, laid down at some distance from each other, in the same strait line continued: and that he had even performed this, without touching the stone with either of the bars, and only by placing it, in the manner just mentioned, between their poles, at the distance of about a quarter of an inch from either of them.

[[left column]] To make artificial magnets. [[/left column]]
[[underline]] A Method of making Artificial Magnets without the use of, and yet far superior to, any natural ones. [[/underline]]
Procure a dozen bars, six of soft steel, each three inches long, one quarter of an inch broad, and one twentieth of an inch thick, with two pieces of iron, each half the length of one of the bars, but of the same breadth and thickness; and six of hard steel, each five inches and an half long, half an inch broad, and three-twentieths of an inch thick, with two pieces of iron of half the length, but the whole breadth and thickness of one of the hard bars: and let all the bars be marked with a line quite round them at one end.
[[left column]] Step... 1. [[/left column]]
Then take an iron poker and tongs (*) (Fig. 2.) the larger they are, and the longer they have been used, the better; and fixing the poker up right between the knees, hold to it near the top one of the soft bars, having [[strikethough]] one of [[/strikethrough]] its marked end downward, by a piece of sewing silk, which must be pulled tight with the left hand, that the bar may not slide: then grasping the tongs with the right hand a little below the middle, and holding them nearly in a vertical position, let the bar be stroked by the lower end, from the bottom to the top, about ten times on each side, which will give it a magnetic power sufficient to lift a small key at the marked end: which end, if the bar was suspended on a point, would turn toward the north, and is therefore called the north pole, and the unmarked end is, for the same reason, called the south pole of the bar.
[[left column]] Step... 2. [[/left column]]
Four of the soft bars being impregnated after this manner, lay the other two (Fig. 3.) parallel to each other, at the distance of about one-fourth of an inch, between the two pieces of iron belonging to them, a north and a south pole against each [[strikethrough]] other [[/strikethrough]] piece of iron: then take two of the four bars already made magnetical, and place them together, so as to make a double bar in thickness, the north pole of one, even with the south pole of the other; and the remaining two being put to these, one on each side, so as to have two north and two south poles together, seperate the north from the south poles at one end by a large pin, and place them perpendicularly with that end downward, on the middle of one of the parallel bars, the two north poles towards its south, and the two south poles towards its north end: slide them backward and forward three or four times the whole length of the bar, and removing them from the middle of this, place them on the middle of the other bar as before directed, and go over that in the same manner; then turn both the bars the other side upward, and repeat the 

(*) Or two bars of iron.

[[right bottom corner]] former [[/right bottom corner]]

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