"Insert Coins for Lumps of Coal: A Brief 2000-Year History of Vending Machines"

From 99% Invisible:

Nearly two millennia before slotted quarters begat cigarettes or snacks, the world’s first vending machine poured out portions of holy water thanks to mathematician and engineer Heron of Alexandria.

Heron (AKA Hero) was an avid experimental designer who dabbled in all kinds of things. He was ages ahead of his time, designing early rocket and steam engines, wind-powered devices, force pumps and other mechanically sophisticated inventions.

The vending machine may not have anticipated quite such epic developments as steam-driven trains or space-age rockets, but it did hint at something that would become widespread in the post-Industrial era. Much like modern versions, his device involved dropping a coin in a slot. That coin would weigh down a pan attached to lever, which in turn opened up a valve. As the pan tipped, the coin slid back off of it and a counterweight returned the mechanism to its original configuration, turning off the flow.

Like many Roman Empire technologies, the vending machine was long lost to history. Such devices would not resurface until the 19th century. Early modern vending machines in late 1800s London sold postcards and stationery, followed by ones in Germany vending chocolates and others in the United States dispensing both candies and figurines — ideas which have persisted and evolved. From there, though, vending machines also branched out in a series of wild new directions....

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