Steel plough e incandescent light bulb: o que têm em comum

1. Passo 1. Steel plough — evoluiu de — Plough. A steel share.
2. Passo 2. Plough — evoluiu de — Hoe. The plough mechanized loosening the soil with a hoe.
3. Passo 3. Hoe — é feito de — Stone. The working part was of stone or antler.
4. Passo 4. Stone — é material para — Oil lamp. The first lamps were stone bowls (Lascaux).
5. Passo 5. Oil lamp — evoluiu para — Incandescent light bulb. The electric lamp replaced oil and gas lamps.

Abrir Evothings