This form of coil was patented in 1903 by Sir Oliver Lodge and A M Lodge. It is used for producing the spark to ignite the explosive mixture of fuel and air in the internal combustion engine of a car. The spark is unaffected by the presence of soot, oil or moisture, and the apparatus would operate even if the sparking points were wholly immersed in water, or the mixture was very weak. This particular example was for use in a multi-cylinder engine.
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