Inventions That Made Human Life Easier and More Social

The Telephone

People had long tried to send signals with messages using bonfires and reflections in mirrors. The Frenchman Claude Chappe coined the word telegraph in 1793 — literally, “writing from afar” — to name his message machine. Movable arms mounted on towers signaled letters and numbers. Over the next 40 years, electric telegraphs appeared, and in 1876 Alexander Graham Bell invented the telephone, which made it possible for the first time to send speech through wires.

Bell’s work with deaf people sparked his interest in studying how sounds are produced by vibrations in the air. His research into a device called the “harmonic telegraph” led him to discover that an electric current could be modified so that it resembled the vibrations of the voice. This was the principle on which his telephone was based.

Recordings

Sound was recorded for the first time in 1877 on an experimental machine that Thomas Edison (1847–1931) hoped would be used to turn telephone calls into telegraphic messages. It recorded calls by making notches on a strip of paper that passed under a stylus. Edison noticed that when the paper was passed through the machine again, a faint echo of the original sound could be heard.

This mechanical-acoustic method remained in use until the appearance of electrical systems in the 1920s. Magnetic principles were used to develop tape recording systems. These received their first commercial boost in 1935, with the appearance of plastic magnetic tape, and later, in the 1960s.

Internal Combustion Engine

The internal combustion engine revolutionized transportation almost as much as the wheel. For the first time, there was a small and relatively efficient machine that made production possible, from automobiles to airplanes. Inside these machines, fuel is burned to produce energy.

The fuel burns inside a tube called a cylinder, produces hot gases as it burns, and these push a piston down the cylinder. The movement of the piston produces the force that moves wheels or machinery. In 1859, the Belgian inventor Étienne Lenoir (1822–1900) built the first internal combustion engine. It was powered by gas.

The German engineer Nikolaus Otto (1832–1891) made an improved engine in 1876. It used four movements of the piston to produce energy and became known as the four-stroke engine. It was later developed by Gottlieb Daimler and Karl Benz, leading to the production of the first automobile in 1886.

Cinema

In 1824, the English physician P. M. Roget was the first to explain the phenomenon of “persistence of vision.” He observed that, if an object is seen in a series of very similar positions in rapid sequence, the eyes tend to see a single moving object.

It did not take long to understand that a moving image could be created from a series of still images, and 10 years later scientists around the world developed various devices to create this illusion. Most of these were merely novelties or toys, but, combined with improvements in lighting systems and the development of photography, they helped advance film technology.

The first successful exhibition of moving images using cinematography was carried out in 1890 by two French brothers, Auguste and Louis Lumière. The pair created a combined camera and projector, the Cinématographe, which recorded images on a strip of celluloid.

Radio

Guglielmo Marconi invented the first radio while experimenting in his parents’ attic in Bologna, Italy. Fascinated by the idea of using radio to send messages through the air, he created an invention that would change the world by making long-distance communication possible and transforming the entertainment business.

As a transmitter, he used an electric spark generator invented by Heinrich Hertz. Its radio waves were detected by a “coherer,” an idea developed by the Frenchman Édouard Branly. The coherer converted radio waves into electric current.

Marconi made an electric bell ring by sending radio signals across the room. It was 1894; by 1902, eight years later, he had sent radio messages 4,800 km across the Atlantic.

Inventions for the Home

Michael Faraday (1791–1867) discovered how to generate electricity in 1831. But many years passed before electricity reached homes. At first, mansions and factories installed generators and used electricity for lighting. The electric filament lamp was tested in 1879. In 1882, the first large electric power station was built in New York.

Little by little, people began to understand that appliances could save work in the home, and mechanical tools, such as the first vacuum cleaners, were replaced by more efficient electric versions. As households increasingly had to do without domestic service, labor-saving appliances became popular.

Around 1920, electric motors were used in mixers and hair dryers. Around this time, the electric kettle, electric stove and electric heaters appeared. Some of them are similar to those used today.