Industrial+technology+PM

=Industrial Technology= In this time, things where made like Trolleys,Skyscrapers and bridges. most building in the 1800's where about 4-5 stories high. They were not so tall because it required to have more resources a the bottom to maintain the height and weight so it wouldn't topple over. That changed because steel companies began to mass produce cheap steel cables and griders. THey used steel cables for the bridges. engineers used the steel cables to suspend bridges to steel towers with the thick steel cables. In 1852, elevators where first made. Then about 30 years after that, the first electrical elevator was made.