Dig into the history of the construction of the iconic Brooklyn Bridge and how John Roebling designed a hybrid suspension system to build it. — In the mid-19th century, suspension bridges were collapsing all across Europe. Their industrial cables frayed and snapped under the weight of their decks. So when German American engineer John Roebling proposed building the largest and most expensive suspension bridge ever conceived, New York City officials were understandably skeptical. Alex Gendler details the building of the iconic Brooklyn Bridge. Lesson by Alex Gendler, directed by Jeremiah Dickey.