From the History of Electricity

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Active Words and Expressions

at rest – в состоянии покоя static – статический, не динамический condition – режим in motion – в движении flow – струиться, течь as well as – так же как, а также behaviour – режим (работы) previously – ранее rubbing – трение, натирание substance – вещество, нечто реальное discharge – разряжать(ся) in no time – быстро unlike charges – разноименные заряды electric current – электрический ток try the experiment – проводить эксперимент

generate – вырабатывать unit – единица измерения continuous current – непрерывный ток dissimilar metals – разнородные металлы steady – неизменный, постоянный to increase – увеличивать, усиливать thus –так, таким образом voltaic – гальванический pile – батарея layer – слой copper – медь moisten – увлажнять, смачивать wire – электрический провод

There are two types of electricity, namely, electricity at rest or in a static condition and electricity in motion, that is, the electric current. Both of them are made up of electric charges, static charges being at rest, while electric current flows and does work. Thus they differ in their ability to serve mankind as well as in their behaviour.

Let us first turn our attention to static electricity. For a long time it was the only electrical phenomenon to be observed by man. As previously mentioned at
least 2,500 years ago, or so, the Greeks knew how to get electricity by rubbing substances. However, for practical purposes static electricity was not much more useful than lightning. Indeed, the electricity to be obtained by rubbing objects cannot be used to light lamps, to boil water, to run electric trains, and so on. It is usually very high in voltage, difficult to control; besides it discharges in no time.

As early as 1753, Franklin made an important contribution to the science of electricity. He was the first to prove that unlike charges are produced due to rubbing dissimilar objects. To show that the charges are unlike and opposite, he decided to call the charge on the rubber – negative and that on the glass – positive.

In this connection one might remember our Russian Academician Petroff. He was the first to carry on experiments and observations on the electrification of metals by rubbing them one against another. As a result he was the first scientist in the world who solved that problem.

So far, almost nothing was said about the electric current. Who does not know that the first man to produce it was Volta. His discovery developed out of Galvani’s experiments with the frog. Various writers retell that story in quite different ways. In fact, Galvani observed that the legs of a dead frog jumped as a result of an electric charge. He tried his experiment several times and every time he obtained the same result. He thought that electricity was generated within the leg itself.

This thought was not so very strange because he could not help remembering the electric fish which possessed the property of giving more or less strong shocks.

As previously mentioned, the discovery of the electric current was made possible owing to Volta after whom the unit of electric pressure, the volt, was named.

Volta was born at Como, in Italy, February 18, 1745. For some years he was a teacher of physics in his home town. Later on he became professor of natural sciences at the University of Pavia. After his famous discovery he travelled in many countries, among them France, Germany and England. He was also invited to Paris to lecture on the newly discovered chemical source of continuous current. In 1819 he returned to Como where he spent the rest of his life. Volta died at the age of 82.

Volta took great interest in Galvani’s researches. He began to carry on similar experiments and soon found out that the electric source was not within the frog’s leg itself, but was the result of the contact of both dissimilar metals used during his observations. However, to carry on experiments of such a kind was not an easy thing to do. He spent the next few years trying to invent a source of a steady, continuous current. To increase the effect obtained with one pair of metals, Volta increased the number of these pairs. Thus the voltaic pile consisted of a layer of copper and a layer of zink placed one above another with a layer of flannel moistened in salt water between them. In this way the voltaic pile looked like a thick sandwich containing copper, zinc, flannel moistened in salt water, copper, zinc, flannel, and so on. A wire was connected to the first disc of copper and to the last disc of zinc.

The year 1800 is a good date to be remembered: for the first time in the world’s history a steady, continuous current was generated.

1. Translate the following sentences paying attention to the Infinitive:

1. We shall translate this article. 2. Do you know this man? 3. They can translate this text without a dictionary. 4. To translate this article is not an easy thing to do.
5. We want to translate this article. 6. I remember to have seen this man last year.
7. To study much is to learn much. 8. To master a language one must work much.
9. The professor to deliver a lecture at our Institute lives in our street. 10. The experiment to be carried on is described in this article. 11. Can this work have been done in such a short time? 12. He must be reading a newspaper in the reading-room. 13. He was glad to have been traveling in Europe.

2. Translate the following sentences paying special attention to the words in bold type:

1. The students carried out an experiment looking at the thermometer from time to time. 2. The cinema was invented before my time. 3. It is high time to begin work. 4. Four times three is twelve. 5. “Am I late?” “No, you are just in time ”.
6. “What is the time?” “It’s dinner time ”. 7. The students went to the club and had a good time there. 8. It took a long time before people learnt to split the atoms.
9. I shall be back in no time. 10. For a long time people did not know that lightning and atmospheric electricity are one and the same thing. 11. Lomonosov lectured at the University and at the same time worked in different fields of science. 12. I work in the laboratory two times a week.

3. Translate the following sentences paying special attention to the Infinitive:

1. This is the device to be used in our experiment. 2. The thermometer is a device to measure the temperature. 3. Where are the articles to be translated by the students? 4. The letter to be answered was given to me. 5. The motor is a device to change mechanical energy into electric energy. 6. Russia was the first to use atomic energy for peaceful purposes. 7. Petroff was the first scientist to study the electrification of metals by rubbing them. 8. I was the last to answer the teacher’s questions.

4. Fill in the blanks with the words one or for:

1. Moscow is … of the largest cities in the world. 2. … must remember that it is necessary to study English at least an hour a day. 3. As … rubber it was brought to Europe as early as the 15^th century. 4. … understands the importance of electricity when … sees trams, trolley-buses and trains driven by it. 5. The energy of the atom is used … peaceful purposes in our country. 6. … must know the chemical properties of the atom. 7. We produce rubber … it is quite necessary … the development of our industry. 8. In 1819 Volta returned to Como … he wanted to spend the rest of his life there. 9. There is a more important problem than that …. 10. I haven’t got a dictionary, I must have ….

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