Wrinkles in Electric Lighting

CONTENTS.

The Electric Current, and its Production by Chemical Means.
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Production of electric current in chemical battery—Current very weak—Current compared to circulation of the blood—Strength and volume of current—Pressure not sufficient without volume—Action of current is instantaneous—Resistance to the passage of the current—Copper the usual metal for conductors—Heat produced by current when wire is too small	1

Production of Electric Currents by Mechanical Means.

Magneto-Electric Machines.

Current produced by mechanical means—Alternating current—Magneto-electric machines—Shock produced by interruption of current—The current must be commutated—Description of commutator—Current, though alternating in the dynamo, is continuous in the circuit—Continuous current used for electro-plating	5

Dynamo-Electric Machines.

Current will magnetise an iron or steel bar—Permanent magnet—Electro-magnet—Where the magneto and dynamo machines differ—Armature of so-called continuous-current dynamo—Type of commutator—Commutator brushes—Current continuous in the circuit—Alternating-current dynamos—Current not commutated—Intense magnetic field produced—Simplicity of Ferranti armature—Large number of alternations of the current—Alternating current cannot be used to excite an electro-magnet—Exciter coupled on to same spindle as dynamo—Power of exciter if used alone	9

Electric Lamps.

Production of electric light—Arc lights—Mechanism to regulate carbons—Some lamps suitable for alternating current—When carbons are consumed, light goes out—Arc lamps very complicated—Jablochkoff candles—Arc formed between the carbons—Candles require alternating current—Incandescent lamps—Vacuum formed in lamps prevents combustion—Vacuum not perfect—Advantages of incandescent lamps for house and ship lighting— Clyx.com