Category Invensions & Discoveries

When was the hydrofoil invented?

The hydrofoil, a boat supported clear of the water by underwater wings called hydrofoils, was invented by an Italian, Forlanini, in 1898. In 1918 a hydrofoil, powered by an aircraft engine, gained the world’s water speed record. The commercial hydrofoils now used in Europe are based on the work of German engineers who carried out research into the design of high-power, lightweight engines.

       In the early 1950s hydrofoils were developed in the United States, Canada and Russia using high-powered gas turbines. They are used for both military and commercial purposes.

     Since water is 775 times heavier than air, very small hydrofoil wings will support relatively heavy boats. But, since operating in water puts great loads on boats, the hulls are usually built of high-strength steel.

    The object in raising the hull of the hydrofoil from the water is to avoid the resistance caused by friction and drag. This means the power needed to drive the boat at high speeds is cut by half. Another result is that the hydrofoil travels smoothly in quite rough water, and is not slowed down.

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Who invented the jet engine?

The first flight by a jet-propelled aircraft was made in Germany on August 27, 1939. Its engine was designed by Hans-Joachim von Ohain, who had conceived the idea while a student at Gottingen University in Lower Saxony. Unknown to von Ohain, the British inventor and aviator Frank Whittle had thought of the idea some years earlier. But his engine did not have its first flight until May 14, 1941.

    Briefly, a jet engine takes in air from the atmosphere, compresses it, and uses it in burning fuel. The mixture of hot gases is then expelled through a nozzle in a powerful backward jet which propels the aircraft forwards.

     This forward thrust is the effect of a scientific principle first explained by the English scientist Sir Isaac Newton (1642-1727). He pointed out that with every action there is a reaction which is equal but opposite to it. Thus when a gun is fired, the forward movement of the shell is matched by the backward recoil of the barrel. In a similar way the reaction to the jet exhaust drives the engine forward. The thrust is obtained by the pressure of the jet against the inside of the nozzle and not, as many people suppose, by the exhaust gases “pushing” against the atmosphere.

     The jet engine, whether turbojet, turboprop, ramjet or turbofan, weights less than a piston engine of comparative power and can be much more streamlined.

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When was the telephone invented?

Alexander Graham Bell (1847-1922) invented and patented in 1876 the first telephone that was of any real practical use. In 1874 he said: “if I could make a current of electricity vary in intensity precisely as the air varies in density during the production of sound, I should be able to transmit speech telegraphically.” This is the principle of the telephone.

      On March 10, 1872, the first historic message was telephoned to Thomas A Watson, Bell’s assistant, who was in another room: “Mr. Watson, come here; I want you.”

     Bell’s first machine gave electrical currents too feeble to be of much use for the general public. In 1877 the American scientist Thomas A. Edison (1847-931) invented the variable-contact carbon transmitter, which greatly increased the power of the signals.

    The telephone was immediately popular in the United States, but Bell found little interest in Britain when he visited the country in 1878. Then Queen Victoria asked for a pair of telephone and the royal interest resulted in a London telephone exchange being formed in 1879 with eight subscribers.

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When were the museums started?

          A museum is an institution that collects, studies, exhibits and conserves objects for cultural and educational purposes. They are of several kinds. There are museums devoted to art, science, history, industry and technology.

          The word ‘museum’ comes from the Greek word Mouseion which means ‘temple of the Muses’. The Muses were the goddesses of the arts. One of the first institutions, called Mouseion was founded in Alexandria, Egypt in the 3rd century B.C. Its aim was to collect information that might be of some interest to the scholars. The scholars used to live and carry out their research there. The museum displayed a collection of art pieces and antiquities like statues, astronomical and surgical instruments, elephant tusks and hides of rare animals.

          Later kings and nobles started having their own museums by collecting art objects and antiques from different parts of the world. However, these were private museums, meant only for their families and friends.

          After the French Revolution the doors of the French museums were opened to the general public. In 1793, during the revolution, the Republican Government established a national museum in Lauvre, Paris. For the first time in the 19th century buildings were specially designed for this purpose. One of the first buildings in Europe was the Atles Museum in Berlin, Germany. It was constructed in 1830.

          Today, we have museums in almost all the big cities of the world. They are visited by thousands of people everyday. The oldest museum in the world is the Ashmolean Museum in Oxford which was built in 1679. The largest museum in the world is the American Museum of Natural History in New York. It was founded in 1874. The largest and the most visited museum in the United Kingdom is the British Museum which was opened for public in 1759. Bombay, Madras, Delhi and other big cities in India have museums devoted to different subjects. 

Who developed the shorthand?

          Shorthand is a system of writing fast using characters, abbreviations or symbols for letters, words or phrases. Other names for shorthand are stenography (little or narrow writing), tachygraphy (swift writing) and brachygraphy (short writing). Because of its obvious usefulness, today it is widely used in business, industry and other professions of the world.

          Most historians trace back the origin of shorthand to the Greek historian Xenophon who used an ancient Greek system to write the memoirs of Socrates. Marcus Tullius Tiro of Rome invented the Latin shorthand far back in 63 B.C. He also compiled a dictionary of shorthand. 

          However, the systematic development of shorthand took place in the 17th century. John Willis is considered the father of modern shorthand. Later the industrial developments brought in a demand for stenographers in the business. During the 18th century several shorthand systems were developed but the one developed by the English stenographer Samuel Taylor in 1786 was adapted in French, Spanish, Portuguese, Italian, Swedish, German, Dutch, Hungarian and other languages. Sir Isaac Pitman developed the modern system based on Taylor’s system in 1837. It consisted of 25 single consonants, 24 double consonants and 16 vowel sounds.

          Irish born John Robert Gregg developed another system in 1888 which was based on circles, hooks and loops. In 1893 this system was introduced in U.S.A. In the present century rapid strides have been made in this field.

           Nowadays many machines are also available which can record fast speeches. Stenotype machine was invented by Ward Stone Ireland, a U.S. stenographer and court reporter, around 1906. This machine is used for recording speeches. It is especially employed for conference and court reporting.

When was the stethoscope invented?

           A stethoscope is a device used by physicians to listen to the sounds inside the body. Generally, these sounds originate from the heart, lungs, abdomen and the blood vessels. Very often valuable information about the disorders in certain parts of the body can be obtained through observing the change in sounds. For instance, a change in the sounds made by the rushing of blood through the heart valves or by the closing of valves may give important clues to different heart diseases. Similarly, an abnormality in the sounds made by air in the windpipe and airways in the lungs may indicate certain lung disorders.

           Stethoscope was invented by a French doctor, Rene T.H. Laennec, in 1815. It was a one-foot-long hollow wooden cylinder. He put one end of the cylinder on to his patient’s chest and listened to the sounds produced by the heart and the chest through the other end. As he compared such sounds from different patients, he could reach certain conclusions. In 1819, he published these conclusions in the form of a book entitled, De L’ Auscultation Mediate, and soon stethoscope came into general use.

            Since those days, many modifications have been made in its design. A modern stethoscope basically consists of a contact piece called the chest piece. This can be a flat chest piece for high-pitched sounds or a bell-shaped open-ended chest piece for low-pitched sounds. It conducts sounds through two flexible rubber or plastic tubes to a pair of ear pieces which fit into the physician’s ears and excludes other sounds. The chest piece is put in contact with the different parts of the chest and the back. Now, through these sounds the physician gets valuable clues regarding the different diseases the patient might be suffering from. The stethoscope is still the simplest and the most useful means available to doctors to examine the lungs and heart.