Civilization manualBook 1: From Bare Hands to Steam and Electricity765 entries · 23 phases · 100 years
The Island
Phase 02 — Stone, bone, wood and fibre toolkit  /  About year 1
02.07

Ground stone axe head

tough polished edge that does not shatter

MakingYear 1Story day 16Stands on 2 earlier

AWhat it needs

Needs 2 other products.

View

Open a box to see what it needs. A dashed box is a product already drawn in full: click it to jump there. In the org chart, drag to move around.

BWhy

Flint is sharp but brittle: swung against a tree it shatters. A head of tough stone, ground to a smooth strong edge, takes thousands of blows. This is the tool that opens the forest.

CYou need

  • A water-worn cobble of tough, heavy, fine-grained stone that does not flake: basalt, dolerite or greenstone. As long as the hand and half as wide, already roughly the right shape.
  • A hard pointed hammerstone (01.02)
  • The grinding slabs (02.04), sand and water

DSteps

  1. Test the stone: strike it with a hammerstone. It should ring, and the blow should leave only a small white bruise, not a flake scar.
  2. Decide the shape: a flattened oval, widest at the cutting end, tapering to a blunt butt.
  3. Peck it to shape. Tap the surface with the point of the hammerstone, thousands of light blows, each crushing away a little dust. Do not hit hard; hard blows crack it.
  4. Peck both broad faces toward the cutting end so that they meet in a blunt wedge, the same on both sides.
  5. Grind the cutting end on the coarse slab with sand and water, pushing in long strokes and rocking the head a little so the edge comes out gently curved.
  6. Grind both faces equally. The finished edge should have the shape of a pointed arch seen end on, not a knife. A thin edge chips.
  7. Finish the last two finger-widths on the fine slab until it shines.
  8. Leave the butt half rough from the pecking. Rough stone grips the handle.
  9. Make two while you are at it. One always breaks.

EIt worked if

  • The edge is even, centred and smooth, with no flat spots or chips.
  • It bites into green wood and comes out unmarked.

FWhat goes wrong

  • It cracks in two while pecking. A hidden flaw, or blows too heavy. Start another; use the broken half for a small chisel.
  • The edge chips in use. It was ground too thin. Regrind it blunter.
  • The edge is off to one side. One face was ground more than the other. Count the strokes on each face.
  • Days pass and it is not done. That is normal. Grind in shifts, and talk while grinding.

GIn the story

Luca calls it polishing rocks and complains for four days. The camp takes turns at the slab in the evenings, and it becomes the place where people talk. When the edge finally shines, Luca holds it up to the fire and stops complaining.

HFigures

not drawn yet
Fig. 02.07-aThe head from the face, the side and end-on, showing the curved edge, the pointed-arch section and the rough butt.diagram
not drawn yet
Fig. 02.07-bLuca pecking a cobble with a pointed hammerstone, grey dust on his knees.making
not drawn yet
Fig. 02.07-cTwo people at the grinding slab by firelight, one pushing the axe head, one pouring water.use