Смешали 120 гр 2,5%-го р-ра сульфата натрия и 10 гр 5%-го той же соли. Какова масса сульфата натрия в полученном р-ре?

Several European countries had a few primitive railroads in the mid-1500's. But they were used mainly to bring up wagonloads of coal or iron ore from underground mines. The mining railroads consisted of two wooden rails that extended down into the mines and across the mine floors. Men or horses pulled wagons along the rails.

In the early 1700's, English coal-mining companies began building short wooden railroads to carry coal above ground as well as underground. In the mid-1700's, workers began covering the wooden rails with strips of iron to make them last longer. By the end of the 1700's, English iron-makers began making all-iron rails. These all-iron rails carried wagons with flanged wheels.

Meanwhile, inventors had been developing the steam engine. During the late 1700's and early 1800's, English inventor Richard Trevithick built the first engines capable of using high-pressure steam. He mounted one of the engines on a four-wheeled carriage designed to roll along the track. In 1804, Trevithick used this vehicle to pull 9 tons of iron, 70 men, and 5 wagons along 9 1/2 miles (15 km) of track. Trevithick's invention became the world's first successful railroad locomotive.

English locomotive builder George Stephenson constructed the world's first public railroad, the Stockton and Darlington, which opened in 1825. The line had a distance of about 20 miles (32 km). It was the first railroad to run steam freight trains on a regular schedule. George Stephenson's second railroad was built in 1830. It was 30 miles (48 km) long and operated between Liverpool and Manchester. It was the first line to run steam passenger trains on a regular schedule.

Stephenson also originated the idea that all English railroads should have a standard gauge. The gauge he selected for the railroads he built – 4 ft 8 1/2 in (1.44 m) – was the same as the length of axles on many horse-drawn wagons. This gauge was eventually adopted by most European railroads and by railroads in the USA and Canada.

Engineers and inventors of many countries contributed to the development of engines. In 1825, John Stevens designed the first steam locomotive in the United States. An experimental model of this locomotive ran on a circular track at Hoboken, New Jersey. In 1829, Pennsylvania company tested the first full-sized locomotive to be operated on a commercial railroad in the United States. This locomotive, the Stourbridge Lion, was built in England.

In 1830, a famous race was held between a horse and a steam locomotive, the Tom Thumb. Peter Cooper, New York manufacturer, wanted to convince officials of the Baltimore and Ohio Line to use locomotives rather than horses to pull the trains. The horse won the race after an engine belt had slipped on the Tom Thumb. But this defeat was only a minor setback for the locomotive, often called the “iron horse”.

The first successful steam locomotive to be placed in regular passenger and freight service in the United States made its first run on Christmas Day in 1830. It was built in New York for the South Carolina Canal and Railroad Company and was called the Best Friend of Charleston. Steam railroad transportation in the USA was born and developed very rapidly.

The electric locomotive was introduced in the late 1800's. Many designers contributed to its development. Thomas Edison tested his first model in 1880, and the first electric street car began operating in Germany in 1881. In 1895, the first electric locomotives were placed in regular service on the Baltimore and Ohio Railroad. Many European countries electrified their main lines after 1900, but almost all American railroads continued to use steam trains. By the mid-1900's, some steam locomotives could reach speeds of up to 100 mph (160 kmph) in passenger service. Nevertheless, in the 1930's US railroads began to switch to diesel-electric locomotives, which were more fuel efficient and easier to maintain than steam ones.

Diesel locomotives were introduced experimentally in 1923. The first passenger diesel went into operation in the USA in 1934; the first freight diesels began to be used on American railroads in 1940.

Today, research engineers are working hard to develop locomotives of higher capacity and greater pulling power, which are easier to maintain, which are safer, more reliable and fuel efficient.

After the mid-1800's, railroads started to use steel for rails and cars. Steel rails last 20 times longer than iron ones. All-steel passenger cars were first put into operation in 1907, all-steel freight cars had almost completely replaced wooden ones by the late 1920's. 

Several important inventions after the mid-1800's helped to improve railroad safety. In 1869, American inventor George Westinghouse patented a railroad air brake. In 1873, American amateur inventor Eli Janney designed an automatic car coupler. But these innovations came into wide use on American railroads only after US Congress had passed the Railroad Safety Device Act in 1893. The building of electric telegraph lines in the mid-1800's made block signaling possible. American engineer William Robinson patented the track circuit used in automatic block signaling in 1872, but Robinson's invention was put into common practice only after 1900.

Meanwhile, more and more people traveled by train, attracted by the speed, safety and comfort of railroads. In 1867, American businessman George Pullman organized the Pullman Palace Car Company. The Company manufactured a sleeping car that Pullman designed. By 1875, about 700 Pullman sleeping cars had been in regular service.

Railways were born in the XVIII century, they went through glory and misfortune, and they are still alive after more than 200 years of their existence.

RICHARD TREVITHICK (1771 – 1833), was a British inventor and engineer. He contributed to the development of the steam locomotive.

Trevithick was born in England in the county of Cornwall, a tin-mining region of Britain. As he grew up, he became interested in the steam engines that pumped water from the mines. By the early 1800’s, he had developed a new engine that was soon used in most of the local mines. This high-pressure engine was the model for most later steam engines.

In 1801, Trevithick designed and built a steam-powered carriage that ran on the road. In 1804, he built the first steam locomotive to run on rails. It pulled a load of iron along a railway for horse-drawn cars. In 1808, he exhibited a large locomotive in London. None of his locomotives were financially successful, because they were too heavy for the roads and railways of his time. But Trevithick did prove that steam-powered locomotives could be built.

GEORGE WESTINGHOUSE (1846–1914), was an American inventor and manufacturer. He produced air brakes for railroad cars. Westinghouse was the first to use alternating current for the transmission of electric power.

Westinghouse was born in Central Bridge, N.Y. As a boy, he worked in his father’s machine shop. At 15 he invented a rotary engine. He served in the Union Army and Navy during the Civil War (1861–1865).

By 1866, Westinghouse had already perfected two inventions: a device for replacing derailed cars and a railroad frog, which made it possible for a train to pass from one track to another. His invention of an air brake in the late 1860’s led to the formation of his first company, the Westinghouse Air Brake Company, in 1869. Westinghouse patented hundreds of inventions and organized over 50 companies. He was president of 30 corporations, including the Westinghouse Electric Company.

1. railroad (Amer.)                                     – железная дорога

          to put a ~ into operation                 – пустить ~ в эксплуатацию

          to maintain a ~                               – содержать ~ 

          to run a ~                                        – управлять ~

2. track                                                      – железнодорожный путь

          to design a ~                                  – проектировать ~  

          to lay a ~                                        – прокладывать ~  

3. rails                                                       – рельсы

          wooden ~                                       – деревянные ~

          iron ~                                              – чугунные ~  

          steel ~                                            – стальные ~

          to roll ~                                           – прокатывать ~

4. railroad gauge                                       – железнодорожная колея

          standard ~                                      – стандартная ~

5. railroad line                                           – железнодорожная линия

          main ~                                            – магистраль

          to put a ~ into a regular service     – ввести ~ в постоянную

                                                                     эксплуатацию

6. wagon                                                   – вагон-платформа, вагонетка

7. vehicle                                                  – транспортное средство

          railroad ~                                       – железнодорожный вагон

8. carriage                                                – экипаж, вагон

          railroad ~                                       – железнодорожный ~  

          four-wheeled ~                              – четырехколесный ~

9. car (Amer.)                                          – железнодорожный вагон

          freight ~                                        – грузовой ~

          passenger ~                                  – пассажирский ~

          sleeping ~                                     – спальный ~

10. wheels                                               – колеса

          flanged ~                                      – колеса с ребордой

11. axle                                                   – ось (колеса)

12. engine                                                – двигатель

          steam ~                                         – паровой ~

          diesel ~                                         – дизельный ~

          electric ~                                       – электрический ~

13. locomotive                                         – локомотив

          fuel-efficient ~                               – экономичный ~

          ~ of high capacity                          – ~ высокой мощности

          ~ of great pulling power                 – ~ с большой тягой

14. train                                                   – поезд

          freight ~                                        – грузовой ~

          passenger ~                                 – пассажирский ~

15. schedule                                           – расписание (движения поездов)

16. speed                                               – скорость

          to move at a ~                             – двигаться со ~

          to reach a speed                         – развивать ~

17. air brake                                           – пневматический тормоз

18. automatic car coupler                      – автосцепка (вагонов)

19. block signaling                                 – блокировка

20. track circuit                                      – рельсовая цепь

21. innovations                                      – новшества

22. safety                                              – безопасность

23. glory and misfortune                       – слава и невзгоды

ЗАДАНИЯ К ТЕКСТУ № 1:

Упр.I. Замените подчеркнутые слова синонимами из текста:

1. English coal mining companies built wooden railways to transport coal overland.

2. Wooden rails covered with iron strips lasted much longer.

3. Steam engines were first used on railways in the early 19th century.

4. These engines were installed on four-wheeled vehicles.

5. The idea of ​​using the standard gauge was put forward by G. Stephenson.

6. The caliber chosen was 4'8 1/2".

7. The first American steam engine was made in 1825.

8. Steam transport in the USA developed very quickly.

9. The first electric motors were put into regular repair by the end of the 19th century.

10. In the second half of the 19th century, railroads began to use steel for the manufacture of rails and vehicles.

11. In the late 1920s, wooden wagons were completely replaced with all-steel ones.

12. Speed, safety and convenience attracted many passengers who moved from place to place by rail.

 Упр. II. Соотнесите синонимы:

1. main line

2. wooden rails

3. to design

4. to switch to

5. carriage

6. engine

7. to manufacture

8. to adopt

9. speed

10. glory

11. to select

12. to originate

13. misfortune

14. innovations

15. to use

16. to build

17. timetable

18. passenger car

19. power

20. service

o. trunk line

m. timber rails

a. to project

i. to shift to

h. coach

d. locomotive

p. to produce

e. to accept

c. velocity

t. fame

s. to choose

f. to create

j. bad luck

r. inventions

g. to employ

k. to construct

l. schedule

b. car

n. capacity

q. maintenance

Упр. III. Найдите в тексте английский эквиваленты:

- использовать железную дорогу для перевозки угля

- тянуть вагоны по рельсам

- угледобывающие компании

- транспортировать уголь из шахты на поверхность

- покрывать деревянные рельсы металлическими полосками

- тем временем

- первый успешный железнодорожный локомотив

- расписание движения поездов

- выдвинуть идею

- длина оси конных экипажей

- в конечном итоге

- экспериментальная модель локомотива

- кольцевой железнодорожный путь

- гонка

- убедить официальные власти

- использовать локомотивы вместо лошадей

- небольшое отступление

- поражение

- в качестве эксперимента

- инженеры-исследователи

- более надежный

- служить в 20 раз дольше

- повысить безопасность железных дорог

- изобретатель-любитель

- Закон об использовании устройств безопасности на железнодорожном транспорте

Упр.IV. Заполните таблицу информацией из текста:

YEAR

COUNTRY

INVENTION

1700’s

1804

1825

1829

1830

1867

1869

1872

1873

1895

1907

1923