Elementary Lessons in Electricity & Magnetism

acid action alternate currents amperes anode armature attracted ball battery capacity carbon cell centimetre charge of electricity chemical circuit coil condenser conductor copper current flows deflexion diamagnetic dielectric difference of potential direction discharge disk distance dynamo earth earth's magnetism electric force electrified electrified body electromagnet electrometer electromotive-force electroscope electrostatic energy equal friction galvanometer glass rod gramme heat Hence hydrogen induction influence machines instrument insulated internal resistance inversely kathode knob length Lesson Leyden jar light lines of force liquid machine magnetic field magnetic force magnetic lines magnetic pole measured metal move N-seeking negative charge Ohm's law ohms opposite kinds oscillations pass piece placed plate platinum polarization produced proportional quantity of electricity repelled repulsion rotating round rubbed shown in Fig spark sphere steel strength substances surface tangent tend thin tion torsion balance touched tricity tube turns volts wire zinc