1. COGS!
A long history

2. Introduction.
Hi I’m Michael O’Connor to show you the importance, history and inventions of cogs. Cogs are usually grey. Cogs (otherwise gears) have dated back to the 12th century in Arabia. A man called Al-jazari(I think this is how you spell it) a great engineer. Well I’ll tell you more if we go here

3. Al-jazari (1136 AD-1206 AD)
So as I was saying on the last page al-jazari great inventor was defiantly the best inventor of his time. If all the Arabian scientists had a smart off al would probably come around top five smartest. Al jazari invented most cog or gear mechanisms we use today. The piston, uses a mechanism that he invented. Guess what it was. A water scooper!(yay!). If you look at a piston you can see an up-down motion. With the water scooper the cogs span the spoon like bowl to hold the water with an up-down motion to it. Isn’t that pretty cool. Well let’s go a bit further in time.

4. Leonardo da vinci (1452 AD-1519 AD)
Preferably, one of the best men ever to exist, he revolutionized us forever. He was inventor of anemometer, flying machine, helicopter, parachute, 33-barreled organ, armoured car, giant crossbow, triple barrel cannon, clock, robotic night, self-propelled kart and scuba gear. More information on the clock will be sourced.

5. The Clock
The mechanical clock has two main parts, the mainspring and the pendulum (remember these). The clock is wound with a key, which tightens the mainspring(remembered it?). As the mainspring unwinds, its energy turns the gears which causes the hands to move. The pendulum keeps time and ensures that the gears move at the right pace ; second by second. This is how mechanical clocks work.

6. Why We Need Cogs
If you have not yet seen how important cogs are, well… we wouldn’t have cars, trucks, most land vehicles, some submarines , clocks, most types of robots, treadmills and much, much more. So, as you can see, without cogs we wouldn’t be very civilized, would we now.

7. The End
Well you have to wrap up good things(Not with paper), all good things will wrap up and finish, even bad things will! Well this is a wrap up for my presentation, hope you enjoyed thanks!

8. How a cog works
There are teeth on the cogs( small bumps) that connect to other cogs. Depending on the way the cog is spinning it will work the mechanism normal or backwards.