Unit 16 measuring instruments Gauge

Gauge, sometimes also spelled “gage”, means to estimate the size or amount of something. A gauge is also a tool such as a speedometer inside a car to see how fast the car is going. See the additional examples below:

I wasn’t able to gauge how tall he was from the pictures.

The gauge was broken so I didn't know the temperature was so high.

Unit 17 inventions

CHRISTOPHER CRUISE: Kevlar is another invention that has saved many people from serious injury and death. Kevlar is a fibrous material with qualities that make it able to reject bullets. Added to clothing, the material protects security officers and soldiers across the world.

The fibers form a protective barrier against gunfire. Bullets lose their shape when they strike Kevlar. Those bullets look like mushrooms, and do not enter the body. Most threats to police and security officers come from handguns. They wear Kevlar vests to protect the upper body. Soldiers wear more extensive clothing protected with Kevlar against heavier ammunition.

BOB DOUGHTY: Kevlar might not have been invented had Stephanie Kwolek been able to seek a career in medicine. From childhood, she wanted to be a doctor. But she lacked the money for a medical education.

Today, thousands of people are glad that Stephanie Kwolek became a research chemist. In that job, she developed the first liquid crystal polymer. The polymer was a chemical product that formed the basis for Kevlar.

BOB DOUGHTY: By the nineteen sixties, DuPont already had produced materials like nylon and Dacron. The company wanted to develop a new fiber. Stephanie Kwolek was part of a DuPont research group that asked to work on its development.

Unit 18 types of engines

By 1800 many industries were using steam engines, designed by James Watt (from where we get the electrical measurement - Watt). Richard Trevithick, a Cornish engineer, refined Watts’ invention and after failing to build a steam powered road vehicle, he designed the first locomotive for an Iron Works in Wales. He called it a 'puffer' because of the noise it made, and on its first journey it traveled at almost 8 km/h an hour! Unfortunately, it was so heavy that it broke the rails - it only made three journeys. But it had shown that steam engines could be used to move trains, and speeds began to increase.

The next 130 years can be described as a Golden Age of Steam. Railways were built all over the world, and the size, speed and comfort of trains continued to increase. By 1870 it was possible to cross America by train, and the building of railways in many other countries allowed people and progress to move quickly across the world.

The fastest steam train in the world was The Mallard. This locomotive traveled up and down the east coast of England between London and York, and in 1938 reached 202 km/h.

Although it is still possible to travel on the Trans-Siberian railway, and take the Orient Express from Paris to Vienna, steam trains such as the Mallard or Flying Scotsman, have not traveled regularly for almost 30 years in many countries. Diesel powered locomotives or trains running on electrified lines now run on most railways. Modern trains are cleaner and much faster than steam engines but many people still miss the puffing sound and the romance of steam.