[Cronos]

The calendar is due to the Sumerians.

Timekeeping, the sumerians too and later Indians, chinese for water clocks.

Coal was used for smelting all over Eurasia before the English invented usage of steam power to drive machinery

[alexander_busek]

libertylover did well to supply his "Algebra" with a question mark.

al-jabr is Arabic, and means "the completion."

Regards,