1. Io keep watch over — наблюдать за

2. all-round automation — полная автоматизация

3. To make it possible — делать возможным

METRIC SYSTEM AND ITS ORIGIN (to be read after Lesson 6)

The idea of a universal system of measures and weights dates from long ago,¹ but it was realized only two centu­ries ago. The metric, or decimal system was worked out by the French Academy of Sciences in 1791. How were the units for length and weight defined then?

Two French scientists who were given the task to de­fine these units took one fourth of the distance from the North Pole to the Equator on the geographical meridian which is running through Paris (the distance from Dun­kirk in France to Barcelona in Spain) and divided it into ten million equal parts. One of these parts was called a metre or ""measure". For shorter measurements the metre was divided by ten, for longer things the metre was mul­tiplied by tens.

It was easy to use the same metre for volume. The weight of one cubic centimetre of water was called a gramme. Thus the metric system was created.

Russian scientists played a great part in the spreading of the metric system in Russia as well as in other coun­tries.

As far as in * 1867 D.I. Mendeleyev addressed Russian scientists to help to spread the decimal system. The pro­ject of the law about the use of the metric system in Rus­sia was also worked out by D.I. Mendeleyev.

It should be said, however, that up till ³ the end of the 19th century different units of measurement were used in various countries. In our country the metric system was adopted in 1918, soon after the Great October Socialist Revolution. Now it is adopted by most of the countries. None of the systems of the past can be compared in sim-, plicity to that of our days.

Notes

1. Dates from long ago — возникла давно 2„ as far as in — еще в 3. Up till — вплоть до

PROGRESS OF INORGANIC CHEMISTRY (to be read after Lesson 7)

We shall define inorganic chemistry today as the study of formation, composition, structure, and reactions of the chemical elements and their compounds, except those of carbon. Many will say that this is not the definition of inorganic chemistry alone, but chemistry itself.¹

Indeed, the earlier divisions of chemistry are disap­pearing and the subject is becoming an integrated whole.²

A modern inorganic chemist slightly distinguishes between inorganic, organic, and physical chemistry. He attaches organic groups to a metal atom if it is more con­venient for investigation; he uses any of the available methods of physical chemistry, if necessary for the solution of his problem.

Two facts helped the development of inorganic chem­istry: the growth of the theoretical techniques of quan­tum mechanics and new optical, electrical and magnetic techniques of physical measurement by which structure can be investigated. For a full understanding of the way in which these achievements affected the development of inorganic chemistry, let's make a short survey of the his­tory of the subject.

We may start with 1828, the year in which Wohler,* the pioneer of organic synthesis, showed the interrela­tionship between inorganic and organic chemistry. For the next fifty years inorganic and organic chemistry pro­gressed side by side. The main work in inorganic chemis­try dealt with the preparation of new compounds and the development of methods of analysis. Great numbers of new compounds were being described and important work was being carried out on the determination of atomic weights. The year 1887 may be accepted as the date of appearance of physical chemistry as another branch of the subject. Many research workers were now interested in physical chemistry because it offered the precision which was lacking ⁴ in inorganic chemistry, At the same time, organic chemistry developed into a system in which structure could be determined. Without the technique for such stereochemical investigations inorganic chemistry lagged behind. Thus we find that by this time organic chemistry, because of its system, and physical chemistry, because of its precision, were constantly attracting work ers of inorganic chemistry. People say that facts give a science its substance, but it is the theory which provides its strength. It is owing to the development of the theory that inorganic chemistry has before it such exciting pros­pects at the present time.

Notes

1. not the definition of inorganic chemistry alone, but chemistry itself — не только определение неорганической химии, а Хи­мии в целом

2. an integrated whole — единое целое

3. Wohler (1800-1882) -— Вёлер, Фридрих — выдающийся не­мецкий химик, пионер в области органического синтеза

4. which was lacking — которой не хватало

A GREAT INVENTION OF A RUSSIAN SCIENTIST (to be read after Lesson 8)

Radio occupies one of the leading places among the greatest achievements of modern engineering. It was in­vented by Professor A. S. Popov, the talented Russian scientist, who demonstrated the first radio-receiving set in the world on May 7, 1895. And it is on this day that we mark the anniversary of the birth of the radio.

By his invention Popov made a priceless contribution ¹ to the development of world science.

A. S. Popov was born in the Urals, on March 16, 1859. For some years he had been studying at the seminary in Perm and then went to the University of St. Petersburg. In his student days he worked as a mechanic at one of the first electric power-plants in St. Petersburg which was producing electric lights for Nevsky prospect.

After graduating from the University in 1882, A. S. Popov remained there as a post-graduate at the Physics Department. A year later he became a lecturer in Phys­ics and Electrical Engineering in Kronstadt. By this time he had already won recognition ² among specialists as an authority in this field.

After Hertz had published his experiments proving the existence of electromagnetic waves, A. S. Popov thought of a possibility of using Hertz waves for transmit­ting signals over a distance. Thus the first wireless (radio) receiving set was created. Then Popov developed his de­vice and on March 24, 1896 he demonstrated the transmis­sion and reception of a radiogram consisting of two words: Heinrich Hertz. On that day the radio-telegraphy was converted from an abstract theoretical problem into a real fact. A. S. Popov did not live to see the great prog­ress of his invention.

In its first decrees the Soviet Government planned the development of an industry for producing radio equip­ment, the construction of radio stations. All this was put

into practice * on a scale which had greatly surpassed Lenin's plans for radiofieation of the country.

Popov's invention laid the foundation for further 'in­ventions and improvements in the field of radio engineer­ing. Since that time scientists all over the world have been developing the modern systems of radio-telegraphy, broadcasting, television, radiolocation, radio navigation and other branches of radio electronics.

Radio will find still greater applications in many fields of science and technology.

Notes