1. When measuring the direction of a fixed object: put the compass flat and close to or parallel to the edge of the compass. Slide the turntable so that the hairpin head of the magnetic needle coincides with two points on the red line of the compass base. So as to position that read direction of the layer press by the transparent line.
2. Measure the direction of the furnace: level the compass. Near the edge of the stove. If the furnace is made of iron, it will affect the swing of the magnetic needle, so it should retreat two or three feet vertically. The edge of the compass is parallel to the edge of the stove. Slide the turntable so that the hairpin head of the magnetic needle matches the two points on the red line. Reading direction
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