https://m.youtube.com/watch?v=i802xnrtd0s
https://m.youtube.com/watch?v=-ry_jiAW458
https://m.youtube.com/watch?v=OXOXn_5PtNI
1931- The Empire State Building first opened.
https://m.youtube.com/watch?v=qSQ-LqkabRE
https://m.youtube.com/watch?v=E2eAAlAq9OM
https://m.youtube.com/watch?v=z6oCQ2QdHA0
https://m.youtube.com/watch?v=ShTlZrVUtj8
1949- the patent is filed for the power-driven jackhammer
https://m.youtube.com/watch?v=Yv3RM803bzw