FACTUAL REFERENCE
SPRINGS, WEIGHTS, WATER, AND OTHER POWER SOURCES

A mechanism needs energy.

WEIGHTS
Gravity provides a steady source of potential energy. Raise a weight, then let
controlled descent drive the mechanism.

SPRINGS
Wound springs store energy compactly and make portable clockwork possible.

WATER
Flow and water pressure powered clocks, displays, and automated mechanisms in
multiple historical traditions.

HUMANS
Hand cranks are underrated. Many calculating machines are automatic in their
internal sequence while still relying on a person to provide motive power.

Automation and power are separate questions. "The machine does the sequence" does
not necessarily mean "the machine supplies its own energy."