From The Book of Facts by Isaac Asimov: The Technological World

More Light, Less Sleep
Thanks to the electrical light, Americans today, on the average, sleep 1,2 hours less Americans of six decades ago. A University of Florida report noted that most adults sleep 7,5 hours a day and that about 15% sleep less than 6,5 hours.

Mighty Micro-chip
A chip of silllicon a quarter-inch square has the capacity of the original 1946 ENIAC computer, which occupied a whole room.

World's Smallest Motor
The world's smallest electric motor weighs one half-millionth of a pound ans is smaller than the head of pin. Built by a Californian, William McLellan, the motor measures a sixty-fourth of an inch on all sides. It has thirteen parts and generates one-millionth of a horsepower. It can be seen in an operation
only through a microscope. McLellan built a motor using a toothpick, a microscope, and a watchmaker's lather.

The First Traffic Lights

In 1930, a Detroit policeman named William L.Potts worked out an electric light system that allowed him to control three street intersections from one tower. he picked the colors red, yellow and green because railroads used them. These were the first street traffic lights.

Forces of Attraction
An electron and a positron attract each other in two ways: the electromagnetic attraction of their opposite electric charges, and the gravitational attraction ot their two masses. The electromagnetic attraction is 4,200,000,000,000,000,000,000,000,000,000,000,000,000,000 times as strong as the gravitational. (Of the four known forces-gravitation, weak interaction, electromagnetic interaction, strong interaction- the gravitational force by far the weakest).

The Largest Light Bulb
The largest light bulb was a foot-long 75,000-watt bulb handblown at the Corning Works to celebrate seventy-fifth anniversary of Thomas Edison's invention of the incandescent lamp.