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4m Halal








ELECTRIC currents are usually led from place to place,
at will, by means of conductors called wires. There are a
great many kinds of wires, each adapted to some special

Wires are usually covered with a material called an
insulator, in order to prevent the loss of electric current
due to the wires coming into contact with other bodies or
circuits. Insulators are substances which do not conduct

Wires which are insulated by heavy braids of cotton
fiber and then impregnated with some compound, such as
creosote, are called weather-proof wires, and are best adapted
to outside service, Where they must be exposed to the action
of the elements.

The wires used for interior Wiring in buildings, etc., are
usually insulated with rubber, over which is placed a
cotton braid to protect the rubber.

Rubber cannot well be used as an insulator for all wires,
although its insulating value is very great, owing to the

fact that it deteriorates under many conditions.

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