The first alarm clock could only ring at 4 a.m.
120
The electric chair was invented by a dentist!
122
In the early 1960's, Porsche commercially manufactured farm tractors.
24
The cigarette lighter was invented before the match.
210
More than a billion transistors are manufactured every second.
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Scientists in China have built a prototype high-speed maglev train that is theoretically capable of reaching speeds of up to 1,800 mph (2,900 km/h).
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