Lethal Dose

The pneumatic tube system, no longer in use, but still intact, at the old Columbia Studios:

From wiki: “Pneumatic post or pneumatic mail is a system to deliver letters through pressurized air tubes. It was invented by the Scottish engineer William Murdoch in the 1800s and was later developed by the London Pneumatic Dispatch Company. Pneumatic post systems were used in several large cities starting in the second half of the 19th century, but were largely abandoned during the 20th century.”