In this Nov. 10, 1965 photo, Arthur Exner, electrical engineer at St. Barnabas Medical Center in Livingston, N.J., double checks the hospital’s emergency electrical generating equipment after a massive power blackout the previous evening plunged tens of millions into darkness across the northeastern U.S. and southern Canada for hours. It was soon established that problems with the electrical grid caused the blackout, and St. Barnabas authorities wanted to be extra certain any recurrence of electrical failure on the East coast would not affect the center’s operation. (The Star-Ledger via AP)

See these photos on APImages.com