Iron+and+Steel

Iro n and steel are both usefull materials in construction, and they are both very heavy too. Steel is one of the strongest materials ever, in tension and compression, that´s way it is used to make a lot of structures, in comparison, iron is not that strong in tension, it breaks without warming, but it molds to any shape under certain conditions.

1. Find the meaning of "Wrought Iron" and its uses Wrought iron is a kind of iron which have a low carbon content, is tough and malleable and so can be forged and welded. Items traditionally produced from wrought iron include rivets, nails chains, railway couplings, water and steam pipes, nuts, bolts, horseshoes, handrails, straps for timber roof trusses, and ornamental ironwork.

2. Answer: Do you think metals are "cold" materials? Explain That is a logical common belief, because almost every time you touch a metal you feel it cooler than your hand, and even cooler than any object close to the metal in the same temperature conditions... Then, by some researching, you can find out that: Metals feel cold when you touch them because they are good conductors of heat. They conduct heat away from the skin on your hand and the temperature receptors in your skin register this as a drop in temperature, so the surface of the metal appears to be cool.

**"//the old cast iron buildings died out. I'm not really sure whether the new skyscrapers killed them, or the new esthetics //"**
 * //__Opinion:__//**

First of all "the new things" usually get over the old things just for that reason.... In this case, steel structures shown up as more usefull and sophisticated structures.. With steel you can make bigger buildings like skycrapers, thet can be a reason for people to prefer steel that iron sometimes...


 * Exercises... Sentences**

1.- The **bricklaying** not only determins a visual effect, it can make a stronger or weaker wall. 2.- One thing you must consider not to choose a material is the **weakness**, stronger materials provide more durability and support. 3.-Steel is stronger than iron in **tension**. 4.-Showing the **strecher** face is one of the bricklying methods. 5.-One of the main support for a building is the **column**.