1. WARM-UP 4/9 How do you think steel has affected the growth of cities? Also: If you were absent the Thursday before Spring Break, make sure you turn in your post-test invention description TODAY

2. Review  Edison  Westinghouse  What were some other inventions?

3. The old way to make metal  Iron puddling!  Iron puddler was responsible for heating the iron to the proper temperature to burn out impurities leaving wrought iron  He has control of the final product, not the owner of the factory

4. The Bessemer Process-1856  Henry Bessemer patented the process making the production of steel easier and cheaper.  This led to mass production in the steel industry.

5. The Bessemer Process Process involves injecting air into molten iron to burn off excess carbon and other impurities.

6. The Bessemer Process led to… …the building of the Brooklyn Bridge!!!

7. And also… Skyscrapers! Strong steel means that America’s teeming cities can now grow upwards!

10. But what other innovation can be found in skyscrapers?  Elevators!  Otis Company famous for building elevators in skyscrapers  Allows skyscrapers to be built taller

13. Let’s look a little further into how steel affected cities…

18. Because of Steel The Railroad Industry Expands! Railroads help revolutionize business and industry several ways!

19. Railroads & Industry 1. Provided a faster and practical way to transport goods 2. Lowered the costs of producing goods 3. Created national markets for buying goods 4. Encouraged innovation in other industries

21.  In 1883, the railroads adopted a national system of time zones to improve scheduling. a system we still use today.

22. Let’s now look at how industrialism led to Big Business…

23. Closer Now that you’ve learned more about the Bessemer Process and the effect of steel, what else can you add from your warm-up about how steel affected the growth of cities?