Hii!
Galvanometer was the first instrument to measure even franke amounts of current. It's construction consists of a rectangular shaped coil which is wound over a light metallic frame and is made up of thin insulated copper wires and coiled several times, that is, with large no. of coils. This coil is then suspended with the help of phosphorus bronze strip between the poles of horseshoe magnet. This becomes a movable torsion head. You can refer to books such as S L Arora or H C Verma for easy understanding of this topic.
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