ch we know to be exerted on mag- aginary magnet at the center of the earth, and any throughout the country an announcement of the ap- netic needles at or near the earth’s surface. magnet on its surface, the length of the magnet is so pearance of a large spot on the sun. Through a piece These lines… … line shows the amount of the evening, shortly after Fig. 3_KEW the movement of the mag- sunset, the northwestern net. One of the three mag- sky was so vividly illumi- nets is hung by a silk thread so as to be free to swing nated by a rosy glow that it was at first mistaken for the earth, that its…
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