Mechanics · Vol. I|Controlled fire|c. 1.5 million years ago

Controlled fire

c. 1.5 million years ago

A flame is chemistry you can hold. Evidence of repeated burning in caves used by early humans appears around a million to a million and a half years ago. Cooking made calories cheaper. Light stretched the day. Heat opened cold ground. Fire is the first process that takes a raw material and returns a different one on purpose.

Africa (Wonderwerk Cave and related sites)

Controlled fire — Original plate drawn for this atlas. Not a photograph of a museum object or a copyrighted portrait.

How the mechanism is arranged

A hearth is a controlled chemical reactor: fuel + oxygen, tended so heat stays where you want it.

How it works

Gather fuel, tinder, and an ember (from lightning, or later from friction or percussion).
Feed the ember until it becomes a self-sustaining flame, then tend it.
Use the heat to cook, harden wood, drive animals, or fire clay.

Why it mattered

Cooking increased available energy from food.
A hearth became a social machine: people gathered and stayed.
Heat later made pottery, metals, and glass possible.

What it unlocked

For further study

Berna et al., PNAS (2012). Wonderwerk Cave burnt bone and ash.
Britannica, History of technology. Fire as a foundational technique.

Check

Name two problems fire solved and one new problem it created.