1 янв 1850 г. - Home Security Systems/Alarms
Описание:
Home security systems date back farther than you might imagine. Though moats and armed guards have been in place to protect homes for centuries, with the invention of electricity, the art of home protection was greatly improved. In 1853, the first patent on electro-magnetic alarms meant that businesses and wealthy residents could secure valuables. Magnetic contacts were installed on the windows and doors that, when tripped, would send a signal through the electromagnetic wiring and sound an alarm. These groundbreaking security systems were effective in deterring break-ins from occurring.
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