Knife-edge pivot e sickle: o que têm em comum

1. Passo 1. Knife-edge pivot — faz parte de — Balança. A low-friction pivot for the beam.
2. Passo 2. Balança — é feito de — Stone. Weights were hewn from stone.
3. Passo 3. Stone — é material para — Enxó. The blade of an adze was ground from stone.
4. Passo 4. Enxó — evoluiu de — Stone tool. Neolithic adzes were stone.
5. Passo 5. Stone tool — evoluiu para — Sickle. The first sickles had flint inserts.

Abrir Evothings